Toole, Floyd E — Sound reproduction- the acoustics and psychoacoustics of loudspeakers and rooms

1297 published claims from this book.

• 16-bit CD audio suffices for most program material while 24-bit exceeds delivery needs
• 16-bit CD resolution suffices for most delivery despite 24-bit studio benefits
• 3D-printed quintile heads let designers test headphones across a population distribution.
• A 1969 study predicted modern cinema-sound findings but was ignored
• A blind-versus-sighted test was designed to expose the influence of visual bias
• A commercial reference target derives from flat near-field monitors
• A corporate research group that openly publishes can elevate both science and company reputation.
• A delayed sound can be 10 dB louder and still lose the localization battle
• A doorway’s flex reduces wall stiffness only below 50 Hz without harming sound
• A five-target headphone preference test needed 350 listening trials
• A flat steady-state in-room response boosts high-frequency direct sound
• A flat-response speaker still shows boundary-induced frequency changes in room
• A flawed consumer loudspeaker’s sonic flaws became entrenched studio convention across decades
• A flawed consumer speaker became the recording industry’s standard near-field monitor.
• A headphone target curve descends gradually with frequency and boosts bass.
• A mid-frequency off-axis sag is a common audible attribute of two-way loudspeakers.
• A mono center channel suffices because vision dominates perceived sound location.
• A multichannel system need not compromise stereo quality
• A neutral loudspeaker can emulate many colored loudspeakers via equalization because woofers are minimum-phase
• A pronounced single bass resonance near 40 Hz is preferred over insufficient bass.
• A real center speaker improves dialogue clarity over a phantom center
• A resistive absorber behind the listener solves reflective-wall problems where diffusers fail
• A room appearing to ring at many frequencies actually has only one dominant resonance.
• A room can sound anechoic and reverberant simultaneously
• A shared loudspeaker and headphone target curve solves the Circle of Confusion
• A sharp resonant peak in a room’s steady-state curve predicts prolonged bass ringing.
• A simple high-pass filter can replace elaborate loudness models
• A single boundary reflecting sound off an omnidirectional source creates frequency-dependent interference lobes
• A single gatekeeper listener biases entire group toward his preferences
• A single headphone target curve cannot satisfy all listener preferences
• A single movie mix should translate across cinema, home and headphone playback
• A single steady-state room curve cannot represent what two ears and a brain perceive.
• A spectral flaw echoed across many speakers gets misattributed to the recording.
• A ten-phon level reduction halves perceived loudness
• A transition frequency separates modal from ray acoustical behavior in rooms
• A well-furnished domestic room can already provide acceptable reverberation times for listening.
• A-weighted measurements ignore low-frequency energy that unweighted SPL captures.
• A-weighting won general acceptance while B-weighting was abandoned
• About 1.2 ms of interchannel delay fully displaces a stereo image to one side
• Above 200 Hz the spectral peak, not the ringing, determines resonance audibility.
• Above 500 Hz room curves are predictable from anechoic loudspeaker data
• Above the transition frequency room-curve wiggles are interference, not resonances
• Absorber performance at specific incidence angles matters more than standardized diffuse-field ratings.
• Absorption coefficients above 1.0 reveal the spec is not a simple percentage.
• Absorption dampens modes and enhances any additional room remedies
• Accurate anechoic data plus blind listening tests make psychoacoustic correlations emerge quickly
• Accurate reproduction requires flat response at near-original playback levels
• Accurate soundstage alone cannot satisfy musically without reproduced hall reflections
• Acoustic polarity inversion is clearly audible with certain instruments and styles.
• Acoustical interference differs per off-axis angle and is averaged out perceptually in rooms
• Acoustical interference dips are too unstable to be evolutionary localization cues
• Acoustical interference dips cannot serve as reliable elevation cues
• Acoustical interference is non-minimum-phase but less audible than resonances.
• Acoustical materials alter reflection spectra, invalidating broadband measurements for audibility
• Acoustical treatment historically meant absorption, favoring dead rooms
• Acoustically acceptable rooms require neutral loudspeakers plus acoustical treatment
• Active noise cancellation reduces preferred listening volume, protecting hearing
• Adding absorption reduces seat-to-seat bass variation significantly
• Adding damping to a resonance paradoxically makes it more audible by widening its bandwidth
• Adding extra subwoofers rarely improves bass without controlled placement
• Adding rear channels to stereo does not improve spatial diffusion
• Adding rear speakers at matching angles does not improve spatial illusion
• Additional distributed subwoofers with optimization outperform EQ while using less power.
• Adjacent boundaries alter radiated sound power via acoustical radiation resistance
• Age and accumulated noise exposure degrade even expert listening panel reliability
• Aging degrades listening judgment reliability despite accumulated expertise.
• Air absorption in rooms under 40 cubic meters is acoustically negligible
• Air space behind absorbing panels cheaply improves absorption performance
• All subwoofers are equally fast at 80 Hz and rooms slow them down
• All subwoofers sound equally fast because rooms, not drivers, dominate bass time response
• Amplifier damping factor above 20 produces no audible effect on loudspeaker transients
• Amplitude bumps in transducers imply predictable phase anomalies and time ringing.
• Amplitude panning dominates studio mixing because it gives compact, multi-listener images.
• Amplitude panning fails front-to-back because ear placement suits horizontal localization.
• ANC and PNC headphone performance is standardized as insertion loss measured with pink noise.
• ANC headphones sound quality varies with noise environment and noise reduction performance.
• Anechoic chambers lose accuracy below roughly 80 Hz and require correction.
• Anechoic early-reflections data predict steady-state room curves across rooms and sample variations.
• Anechoic far-field measurements need at least two meters of distance
• Anechoic loudspeaker data reliably predict in-room high-frequency response above 500 Hz.
• Anechoic on-axis and sound power responses suffice to predict perceived loudspeaker quality
• Anechoic-data equalization differs sharply from room calibration, which is often misused
• Anthropometric head quintiles can validate headphone reproducibility at design time
• Artificial manikins can approximate a target population for headphone testing.
• As wavelength shrinks below diaphragm size, speakers beam and off-axis sound diverges spectrally
• At high frequencies rooms act as irregular interference fields rather than standing-wave patterns
• At low frequencies only drivers and ports define a loudspeaker’s effective source size
• Atmos up-firing speakers exploit ceiling bounce because elevation cues are high-frequency.
• Audibility gaps in loudspeakers stem from inadequate measurements, not limitations of measurement itself.
• Audible acoustic polarity effects require the ear’s asymmetric detection process
• Audible distortion in quality loudspeakers is rare within intended limits
• Audible resonance data enables value engineering of cheap loudspeakers
• Audible resonance decay thresholds rise sharply as frequency decreases
• Audible resonances drove low sound-quality ratings in early blind tests
• Audible room deficiencies are rarely caused by comb filtering.
• Audience bass preferences deviate from the Harman target by up to six dB.
• Audience-size scaling corrections in movie sound standards are incorrect
• Audio distortion arises from level-dependent nonlinearity in the device’s transfer function
• Audio electronics can introduce flaws that subjective reviewers misread as virtues
• Audio industry product sign-offs relied on executive taste, not blind testing
• Audio knowledge is best conveyed through discovery history rather than bare facts
• Audio mixers’ occupational hearing loss can impair their sound-quality judgments
• Audio research effort is inverted relative to where people actually listen
• Audio-video interactions grow stronger with channel count and screen size
• Audiometrically normal listeners may still have substantial hidden hearing loss
• Audiophile hardware that omits tone controls harms listeners’ ability to improve sound.
• Audiophile press acclaim and high prices do not reliably predict speakers’ blind-tested performance rankings.
• Auditory streaming explains how listeners separate loudspeaker from room sound
• Automated loudspeaker position switching improves listening-test reliability
• Automatic EQ can create unwanted resonances by filling interference dips
• Automatic equalization can create resonances by filling interference dips.
• Averaged listener ratings can hide hearing-loss-driven individual disagreement
• Axial mode frequencies are computable from room dimensions by a simple formula
• Axial room modes can be predicted from room dimensions alone
• Badly designed loudspeakers cause audible amplifier differences reviewers attribute to the amplifiers
• Bass accounts for roughly 30 percent of perceived sound quality
• Bass extension at −10 dB cutoff predicts loudspeaker fidelity ratings best
• Bass frequencies need far smaller level changes to halve perceived loudness
• Bass level errors cause perceived treble excess and vice versa
• Bass management lets small loudspeakers deliver full-range sound
• Bass management reroutes low frequencies from small speakers to shared subwoofers.
• Bass performance drives roughly 30% of overall loudspeaker sound-quality ratings.
• Bass phase distortion audibility remains unproven without double-blind tests.
• Bass quality dominates overall sound satisfaction yet is room-controlled
• Bass rise in reflected sound is physically unavoidable with forward-firing speakers.
• Bass rises in reflected room sound for all forward-firing loudspeakers
• Bass traps’ inadequacy pushed Toole toward multi-subwoofer mode control.
• Bass-region reverberation-time measurements reflect resonance ringing, not reflected sound
• Belief systems reject disconfirming evidence rather than revising theories
• Belief systems respond to contrary evidence by discounting the evidence
• Bell Labs 1930s tests found three channels sufficed to transmit a soundstage
• Bell Labs recognized multichannel benefits as early as 1934
• Below the transition frequency the room, not the loudspeaker, dominates sound quality.
• Below-1 kHz resonances go unpunished by the prediction model despite lowering actual preference scores
• Beyond about 80 Hz, loudspeaker price governs aesthetics, output and distortion, not timbral accuracy.
• Binaural and crosstalk-cancelled delivery may finally make multichannel practical
• Binaural audio without visuals and head tracking stays internalized in the head
• Binaural headphone tests can replicate real-time loudspeaker listening
• Binaural hearing makes perceptual sense of acoustically chaotic rooms.
• Binaural hearing separates direct and reflected sound while monaural microphones cannot
• Binaural hearing transforms in-room comb filtering into perceived spaciousness
• Binaural recording validity enabled isolating the room-familiarity variable
• Binaural recordings capture nonlinear headphone distortions; virtual methods do not
• Binaural room impulse responses generate spatial audio via convolution
• Bipole but not dipole designs give surround channels needed coverage
• Bipole surround loudspeakers radiate hemispherically to deliver similar direct sound to all listeners
• Blamed loudspeaker tweeter problems may actually originate in the recording microphone
• Blind listener tests reliably favor the most neutral loudspeakers
• Blind listeners largely agreed on loudspeaker preferences, matching measurement quality
• Blind listening shows listeners consistently prefer flat, smooth anechoic frequency response
• Blind listening tests make subjective sound judgments objective and repeatable
• Blind testing found 20% preferred synthesized phantom surround over real speakers
• Blind tests collapse personal preference into shared judgments
• Blind tests group listeners by judgment variability to reveal hearing effects
• Blind tests show any equalization improves subjective loudspeaker ratings
• Blind tests show new violins beat Stradivaris for most soloists
• Blind-tested listeners with normal hearing produce reliable, measurement-grade subjective ratings
• Body and torso acoustics measurably shape the sound reaching the ears
• Bolt’s room-ratio studies targeted reverberation chambers, not listening rooms
• Boundary distances tuned to be unequal and non-multiples minimize frequency-response variations
• Boundary placement boosts low-frequency output by 6 dB per solid-angle halving.
• Boundary reflections create acoustical images that halve the radiation solid angle
• Boundary-image relationships hold only when wavelengths exceed source size and separation
• Brand, cost, and prior exposure bias subjective audio judgments
• British engineering schools restricted colonial students from popular courses even with acceptance letters.
• Broad, low-Q resonances are the most audible transducer defects
• Broadband ETCs are untrustworthy whenever reflections differ spectrally from direct sound
• Brute-force parameter search minimizes seat-to-seat bass variation
• Buffered listening environments mask off-axis loudspeaker flaws and bias evaluations
• Canadian audio magazines contributed test products and journalists to NRCC blind listening tests
• Car cabins create unique acoustics with no ideal listening position.
• Car road noise exceeds music spectra below about 200 Hz
• Carpet underlay type determines whether flooring absorbs sound at all
• Ceiling reflections are as detectable as lateral ones despite weak binaural cues
• Center channel carries most dialog but stereo mixing habits undermine TV use
• Changing room geometry barely alters loudspeaker quality rankings
• Chronic 85 dB daily exposure causes hearing loss, while 130 dB risks acute injury
• Chronic noise exposure causes tinnitus and hyperacusis even with hearing protection
• Cinema playback level disputes have prompted talk of legal limits
• Cinema playback levels are calibrated with pink noise and C-weighting.
• Cinema reference calibration permits volumes so high they drive patrons out.
• Cinema reference level requires 105 dBC peak capability in screen channels.
• Cinema RT targets balance dialog clarity against realistic hall ambience.
• Cinema, not music, has driven every expansion of audio channel count
• Cinema’s non-neutral spectral target forces engineers to compensate and varies across venues
• Cinema’s X-curve standard was based on primitive measurements that ignored better available research
• Classical and solo music are poor for revealing loudspeaker flaws
• Classical music is not superior for revealing loudspeaker resonances.
• Clean amplifier clipping is inaudible until waveforms lose over half their amplitude
• Closing off cavity openings with hard material outperforms absorbing fill.
• Cochlear damage disrupts temporal fine structure needed by the MSO
• Cochlear damage produces distinct perceptual deficits depending on which cell type is affected
• Codec artifacts are faint and need trained ears to detect
• Coincident and spaced microphone pairs encode direction into IAD or ITD cues.
• Coincident delayed sounds are far harder to detect than spatially separated ones
• Coincident pairs produce IAD while spaced pairs produce ITD in microphone recording
• Commercial loudspeaker engineering requires translation across varied sources and listeners
• Commercial room-calibration algorithms vary so widely that results are not directly comparable.
• Commercially sold dipole surrounds were not acoustically true dipoles
• Common tall loudspeakers are not true line sources
• Comparative measurements remain reliable even without absolute low-frequency accuracy
• Comparing three or four loudspeakers at once best exposes timbral differences
• Comparing two sound samples requires accurate auditory memory of a timbral identity.
• Competing recordings of the same work show enormous, sometimes poor, perspective choices.
• Computer-assisted search is needed to optimize bass in non-rectangular rooms
• Concert halls need 1–2 seconds of reverberation balancing loudness against clarity
• Constant Beamwidth Transducer loudspeakers produce astonishingly uniform sound level across listening distance.
• Constant beamwidth transducers deliver uniform sound levels over large areas
• Constant errors normalize away in comparative loudspeaker tests
• Constant-beamwidth-transducer speaker arrays hold stable loudness across listening distance
• Consumer and professional audio must agree on reproduction standards for recordings to translate
• Consumer loudspeaker distortion is masked at normal listening levels.
• Consumer loudspeakers at moderate prices rival professional monitors in sound quality.
• Consumer loudspeakers rated higher than professional monitors in blind tests
• Consumer Reports killed its loudspeaker reviews after research disproved their methods
• Consumer Reports loudspeaker ratings inversely predicted perceived sound quality.
• Consumer Reports loudspeaker ratings lacked rigorous subjective validation
• Consumer Reports rated loudspeakers using sone-converted sound power against an ideal target
• Consumer Reports speaker ratings were negatively correlated with blind-test fidelity ratings
• Consumer Reports’ accuracy scores inversely correlated with actual listener preferences.
• Consumer tone control use disrupts program translation across systems.
• Consumers can judge loudspeaker quality from spinorama curves without hearing them
• Consumers prefer boosted bass, a forgivable audible sin
• Continuous signals flatten reflection detection thresholds while transient signals steepen them
• Control-room design choices rest on preference, not validated science
• Controlled boundary measurements confirm the predicted 6 dB per solid-angle-halving gain
• Controlled measurements confirm the theoretical boundary-gain relationships at low frequencies
• Conventional and bookshelf loudspeakers are engineered for free-standing placement
• Conventional distortion measurements include inaudible masked components
• Conventional distortion metrics cannot predict human response to music or movies
• Corner subwoofer placement maximizes bass efficiency but worsens seat-to-seat consistency.
• Corners are never modal nulls, so corner placement is robust.
• Correlating anechoic data, room response, and blind listening tests is rare and powerful
• Coupler type 4.3 shifts both low and high frequency headphone readings
• Critical distance in concert halls is often only a few rows into the audience.
• Critical distance is ill-defined in small rooms because short reverberation times fail steady state
• Critical listening ability declines with age even for experts
• Critical loudspeaker evaluation should use mono for fail-safe real-world listening
• Critics reject preference testing as mere taste, demanding realism or accuracy instead
• Crosstalk cancellation can expand the stereo soundstage from ±30° to ±90°
• Crosstalk cancellation delivers binaural separation through loudspeakers
• Crosstalk cancellation expands stereo images from ±30° to as wide as ±90°
• Crosstalk cancellation works only within a centimeter-sized listening zone.
• Crosstalk-cancelling filter technology has advanced with head tracking and multi-listener support.
• Cultural and age biases in sound preference are minimal, except for hearing degradation
• Cultural and age preferences for sound do not appear in blind testing
• Curve smoothness and flatness track perceived sound quality ratings
• Curved and Legendre-shaded loudspeaker lines use the floor reflection to achieve uniform broadband coverage.
• Curved, Legendre-shaded line arrays exploit floor reflections to maintain constant beamwidth at all frequencies
• Custom musicians’ earplugs reduce volume without destroying timbre
• Damping factor is the standardized specification for amplifier output impedance
• Damping factor varies from 200-800 for solid-state but only 2-11 for tube amps
• Declared normal hearing can still hide degraded sound-quality opinions.
• Decorative stretched fabric over empty walls turns a room acoustically dead.
• Decorrelation of surround channels solved in-head localization in home theaters.
• Deep broadband diffusers can create a 30 dB immediate reflection drop
• Delayed lateral sound can exceed direct sound by 10 dB before perceived equally loud
• Delayed sounds arriving from different angles are perceived as spaciousness, not comb filtering
• Delayed, inverted subwoofer arrays can cancel standing waves in rectangular rooms
• Dense early reflections sum perceptually to sound livelier than energy measurements predict
• Design priorities determine which subwoofer-seating configuration optimizes a room.
• Desirable room acoustics can be encoded and delivered digitally rather than built
• Detecting reflected sound depends heavily on the continuity of the source signal
• DF headphone calibration avoids conflicting HRTF localization cues that make FF sound unnatural
• Different equal-loudness contour studies disagree substantially in shape
• Different loudspeaker topologies each produce characteristic on- and off-axis flaws.
• Diffuse-field regions sound best because modes are minimal and level is even
• Diffuse-field targets are least preferred, but adding bass improves them
• Diffused artificial reverberation matters more than reverberation time for musical satisfaction
• Diffuser depth sets a lower frequency below which no scattering occurs.
• Diffusers mainly attenuate specific reflections rather than create diffuse fields
• Diffusers manipulate only part of the spectrum and can act as absorbers when fabric-covered
• Diffusing surfaces may not reduce perceived reflection loudness as expected
• Diffusing surfaces serve performance spaces, not home reproduction rooms.
• Diffusion terminology is routinely misapplied to small rooms
• Diffusor effectiveness in small listening rooms lacks subjective validation
• Digital headroom led cinema sound to destructive loudness levels
• Digital post-processing enabled low-frequency calibration of anechoic chambers.
• Digital processing makes measurements better approximate what we hear
• Dimensional room symmetry does not guarantee acoustic symmetry
• Dimensionally symmetrical rooms are acoustically asymmetrical due to construction details
• Dipole surround speakers degraded direct sound without creating effective diffuse fields.
• Dipole surrounds only worked for one row of listening positions
• Direct sound determines localization, loudness, and perceived spectrum quality
• Direct sound governs perceived quality in rooms, not room curves
• Direct-sound-dominated rooms maximize the stereo center-image spectral distortion
• Directivity mismatch at crossover frequency causes predictable dips in sound power
• Directivity, not equalizable response, is the fixed determinant of loudspeaker sound.
• Discrete quadraphonic LP technology improved conventional two-channel record quality.
• Distinctly different headphone frequency responses can all be equally preferred
• Distortion rarely drives subjective ratings of consumer loudspeakers
• Dolby’s 100 Hz Atmos crossover risks localizing subwoofers but is accepted for simplicity
• Double bass arrays keep high efficiency despite half the units cancelling
• Double-blind evaluation can identify the most transparent loudspeakers
• Downmixing across channel counts remains an unresolved delivery problem.
• Downmixing metadata adapts recordings but customers learn nothing of the compromises
• Each 10 dB of level requires ten times the amplifier power
• Ear coupling and head size make headphone sound-quality opinions vary widely
• Ear protection alone does not fully prevent cumulative hearing damage
• Ear simulator corrections depend on the headphone’s own acoustic load
• Ear-drum reference point measurements are clinically risky and unreliable at high frequencies
• Ear-level microphone measurements capture artifacts inaudible to human listeners
• Ear-tip insertion depth shifts canal resonance upward by several kilohertz
• Early binaural headphone studies localized sounds inside the head rather than externally.
• Early blind loudspeaker comparison relied on single overall preference ratings
• Early lateral reflections are attenuated by loudspeaker directivity, not harmful.
• Early lateral reflections are not necessarily audible problems in stereo listening
• Early listening tests required repeated short passages heard through every loudspeaker.
• Early loudspeaker preference studies were too crude to validate any measurement model
• Early mid-century radios sounded small, colored, and lacking in bass
• Early recording technology forced performers and dead-acoustic studios as standard practice
• Early recording technology stripped music of all sense of space
• Early reflection control often concealed flawed off-axis loudspeaker performance.
• Early reflections are beneficial for recreational home listening but optional to treat.
• Early reflections boost perceived loudness while loud late reverberation degrades intelligibility
• Early reflections within 30-40 ms improve speech intelligibility
• Early room reflections benefit speech intelligibility as much as raised direct sound level
• Early side-wall reflections range neutral to beneficial with well-designed loudspeakers
• Early speaker tests were so flawed any measurement correlated with perception
• Edison staged deceptive live demonstrations to prove his phonograph was tonally transparent
• Edison’s early ‘tone tests’ were staged demonstrations rather than genuine proofs of fidelity
• Effective sound diffusers must be physically comparable in size to the waves they scatter
• Electroacoustic reverberation enhancement systems can invisibly reshape hall acoustics per performance.
• Electronic multi-subwoofer mode control excels because it benefits many listeners at once.
• Elevated hearing thresholds impair spatial separation of direct sound from room reflections.
• Elevated microphones above 400 Hz congregate, reducing seat-related measurement anomalies
• Elevation cues involve increased 7-8 kHz and decreased 12 kHz energy
• Elevation localization is a timbral recognition task driven by resonant peaks
• Elevation localization relies on pinnae spectral cues encoded as HRTFs
• Elevation localization rests on spectral recognition of familiar sounds, not spatial cues.
• Emission cancellation needs 30-50 dB less level than hearing cancellation
• Engineered diffusers attenuate the specular reflection toward the listener by up to 20 dB
• Engineers distrusting blind tests converted upon seeing correlations with their measurements.
• Engineers’ colored monitors embed personal EQ into the recording itself
• Envelopment can be reproduced with few channels, not hundreds
• Envelopment cues below about 80 Hz cannot be reproduced in small listening rooms
• Envelopment cues below roughly 80 Hz are hard to reproduce in small rooms.
• Envelopment in small rooms must come from recordings rather than natural reflections
• Envelopment requires a center channel instead of a symmetric front-back array.
• EQ cannot reduce seat-to-seat variation from a room mode
• Equal-level stereo speakers create a phantom image midway between them
• Equal-loudness contour data have been repeatedly revised and corrected
• Equal-loudness contour measurement evolved from anechoic pure tones to reflective-space noise bands
• Equal-loudness contours are a fixed property of human hearing
• Equal-loudness contours vary greatly across individual listeners
• Equal-loudness contours were first measured using 1 kHz reference tones and phons
• Equalization and listener repositioning can produce nearly identical results for room modes.
• Equalization and mode cancellation both reduce bass resonance ringing despite different mechanisms
• Equalization cannot fix loudspeaker directivity problems because it only changes frequency response.
• Equalization masks a mode’s audibility but only for reproduced sound.
• Equalization only corrects sound at the measured position, not the physical resonance
• Equalizing for a flat in-room response requires adding a high-frequency boost.
• Equalizing only the low-Q resonance substantially improves subjective loudspeaker ratings.
• Equalizing subwoofers individually yields unpredictable combined in-room response
• Equalizing to a universal target curve cannot reliably improve sound
• ETC displays can misreport reflection levels by about 20 dB versus audibility
• ETC spike heights correlate inversely with actual audibility of reflections
• European multichannel loudness experiments matched listener judgments to model predictions.
• Even designer loudspeakers deviate seriously from flat response targets.
• Even expert engineers are biased by non-auditory factors in loudspeaker evaluation
• Even modest hearing loss increases variability in sound quality judgments
• Even professional monitor loudspeakers showed measurable defects in early tests
• Every channel in a multichannel setup must perform well as a solo monophonic source
• Every stage of the audio chain high-pass filters bass, accumulating phase shift.
• Excess uncorrelated rear-wall sound can destroy the phantom center image
• Excessive absorption can degrade speech intelligibility
• Excessive bass is widely tolerated by home audio consumers
• Excessive center-channel upmixing damages music soundstage rendering
• Excessive rear-wall diffusion can destroy the stereo center image
• Executive sign-off and showroom loudness dominated pre-Harman product voicing
• Experimental constraint forced a dipole approximation rather than true omnidirectional speakers
• Fabric covering diffusors can triple their absorption contribution
• Fabric wall coverings often ruin acoustic design despite being advertised as transparent
• Facing forward corrupts center-image timbre due to head-related transfer function errors
• Familiar repeated test music reveals loudspeaker flaws that unfamiliar excerpts cannot
• Far field onset distances vary widely by source size and wavelength
• Fewer-channel arrays were judged against a 24-speaker reference for envelopment impairment
• Fiberglass density barely affects absorption but strongly affects mechanical strength
• Fiberglass reflection depends on angle and frequency, not density
• Fibrous absorbers become ineffective below roughly a quarter-wavelength thickness.
• Film mixes with expanded dynamic range strain dialog intelligibility
• Fine-grained anechoic measurement statistics can near-perfectly predict listener preference rankings
• First-arriving direct sound dominates localization and loudspeaker images are built from mono and double-mono
• Fixed reference loudspeakers can turn their flaws into sought-after virtues
• Flat frequency targets suit binaural audio while Harman suits stereo
• Flat on-axis response alone is insufficient; off-axis sound matters too.
• Flat on-axis speakers naturally produce rising bass power and downward-tilted room curves.
• Flat targets may beat the Harman curve for binaural headphone rendering
• Flat-response speakers unavoidably produce a bass-heavy steady-state room sound
• Flattening sound power via bass-shy or treble-hot designs harms perceived quality
• Flavor should be added at the mixing stage, not baked into the monitoring hardware.
• Flawed studio monitors bake their own coloration into recordings
• Fletcher and Munson’s equal-loudness data are no longer trusted
• Floor reflections are an inherent part of normal human listening
• Floor reflections are perceptually benign and removing them sounds unnatural.
• Floor reflections evolved as a constant cue for spatial judgment
• Flush-mounting in a wall boosts bass output of a loudspeaker not designed for it.
• Flutter echoes can be detected by a handclap test while others listen.
• For hearing-impaired viewers, unclear dialogue makes a movie unenjoyable
• Formal listener training plus experience yields the highest rating reliability
• Forty-four percent of daily headphone users deny hearing-damage risk despite symptoms
• Four mic-speaker pairs can transform a room’s perceived acoustics into a hall.
• Four or five well-placed loudspeakers match the envelopment of 12-to-24 channel arrays
• Frequency and time domain representations equivalently define linear loudspeaker behavior
• Frequency response is the principal determinant of loudspeaker sound quality.
• Frequency response is the single most important measurable parameter of audio devices.
• Frequency response tolerances are meaningless without specifying the bandwidth of deviations
• Frequency-dependent acoustic power output is a loudspeaker’s most audible performance aspect
• Frequency-dependent interaural cross-correlation measures sound-field reconstruction fidelity.
• Frequency-response peaks prove time-domain ringing in minimum-phase devices
• Frequency, phase, and impulse responses are interchangeable transforms of each other
• Frequency, phase, and impulse responses are mathematically interchangeable descriptions of linear behavior.
• Front loudspeakers are designed without regard for their boundary settings
• Full-height line sources halve the off-center damage to envelopment
• Fully steerable loudspeaker arrays are technically feasible but priced out of existence
• Furniture and drapes alone usually achieve the 0.3-0.4 s domestic reverberation target
• Gently rising bass response is both natural and preferred in loudspeakers
• Geometric acoustics fails on diffraction at low frequencies in complex rooms
• Geometric mismatch between cutter head and pivot arm distorts LP playback
• Graphs in audio reviews can deceive by manipulating axis scaling.
• Greater loudspeaker-wall separation shifts the adjacent-boundary dip to lower frequencies
• Group delay detection threshold is 1.6-2 ms
• Group listener sessions bias subjective loudspeaker ratings through social signaling
• Haas measured how much louder a delayed sound could be before dominating localization
• Half-wave rectification in the inner ear does not make polarity reversal audible
• Hall reverberation cloaks loudspeaker defects in live-versus-reproduced demonstrations
• Harman’s calibration target curve encoded deliberately tilted in-room response, not flat room response
• Harmonic distortion measurements poorly predict audible annoyance from real music.
• Head and ear variation makes fixture measurements unreliable predictors of listening
• Head and torso simulators capture spatial cues with microphones at eardrum locations
• Head orientation is necessary because interaural level differences plateau off-midline
• Head related transfer functions anchor sounds to visual cues in VR
• Head shadowing gives roughly 6 dB interaural amplitude difference near 1.85 kHz
• Head-motion-dependent sound changes are required for external sound localization
• Head-mounted measurement adds leakage absent from flat-plate fixtures
• Head-tracking binaural convolution yields convincing externalized spatial audio
• Head-tracking with measured impulse responses strongly improves sound externalization
• Headphone and loudspeaker bass targets converge on the same in-room response
• Headphone bass boosts may compensate for missing haptic sensation from loudspeakers
• Headphone bass perception varies with how well headphones seal on each ear
• Headphone blind tests cannot use automated shuffling, so tactile cues leak into results.
• Headphone calibration shifted from subjective listeners to probe mics and HATS
• Headphone frequency response varies across listeners by up to 9 dB.
• Headphone listening increases agreement with and empathy for narrators
• Headphone measurement variability is greatest below 500 Hz and above 3 kHz
• Headphone measurements vary most between individuals at high frequencies.
• Headphone positioning causes large measurement variation below 500 Hz and above 3 kHz.
• Headphone preference ratings can be predicted from objective measurements like loudspeakers’ can.
• Headphone preference tests can be run virtually via equalization.
• Headphone preference tests used double-blind methods across a wide price range
• Headphone preference tolerances are tightest in the speech-critical midrange.
• Headphone price poorly predicts predicted listener preference across all types
• Headphone reproducibility varies strongly with frequency, worse at bass and treble extremes
• Headphone reproduction lacks the spatial cues loudspeakers in rooms provide
• Headphone retail price shows almost no correlation with sound quality
• Headphone sound preferences are remarkably consistent across countries and ages
• Headphone sound preferences vary by gender, age, and listening experience
• Headphone sound quality depends on fit and acoustic seal around the ear
• Headphone sound-quality variance comes more from user and content variables than target-curve refinements
• Headphone sounds are usually lateralized inside the head.
• Headphone target curves can be derived computationally from HRTFs without a physical reference field.
• Headphone target measurement averages six manikin positions across three angles
• Headphone test-fixture measurements often fail to predict what individual listeners hear
• Headphone-specific corrections can translate target curves between ear simulators
• Headphones are the most common device for experiencing spatial audio content
• Headphones became the primary device through which entertainment is consumed
• Headphones calibrated to semi-reflective room sound best reproduce stereo recordings made for loudspeakers.
• Headphones lack the phantom-center 2 kHz comb notch present in loudspeaker stereo
• Headphones lack the phantom-center timbre notch because no interaural crosstalk exists.
• Hearing adapts in real time to drastically modified HRTFs
• Hearing impairment commonly begins between ages 30 and 44
• Hearing loss impairs spatial sound separation, not just frequency detection.
• Hearing loss makes listener opinions unreliable no matter how experienced
• Hearing loss that harms multichannel dialogue clarity can begin as early as age 30.
• Hearing loss widens critical bands and alters music perception itself
• Hearing-impaired listeners equate speech intelligibility with overall sound quality.
• Hearing-impaired listeners give inconsistent sound-quality ratings unlike normal-hearing subjects
• Hearing-impaired professionals give confident but unreliable sound quality judgments.
• Hearing-normal listeners give far more consistent loudspeaker quality ratings.
• Heating voice coils raises resistance and lowers transducer output
• Hi-fi enthusiasm predicts listening reliability better than musical training does
• Hi-fi enthusiasts judge sound quality more reliably than untrained musicians do
• Hi-fi enthusiasts, not musicians, are the most reliable listeners
• Hidden hearing loss impairs separating sounds in complex acoustic scenes
• High broadband directivity reduces lateral reflection levels in loudspeakers
• High frequency resolution in waterfalls forces poor time resolution that misrepresents room decay.
• High-end audio forfeited credibility by refusing blind testing
• High-end audio wire exploits expectation bias rather than real physics
• High-frequency loss with distance provides a perceptual cue for judging sound source distance
• High-frequency-resolution waterfalls falsely suggest uncontrolled ringing
• High-power loudspeakers often trade timbral accuracy, while accurate ones are limited in level
• High-Q resonances are rarely heard but catastrophically audible when music hits their exact frequency
• High-Q resonances are rarely heard but intensely annoying when triggered.
• High-resolution measurement and matched Q are required for effective modal EQ.
• High-resolution measurement and Q-matched filters are required for effective EQ
• Higher-Q resonances become less audible because music rarely energizes them
• Highly regarded hifi loudspeakers had wildly non-flat anechoic responses
• Highly regarded loudspeakers measured far from flat in anechoic response
• Highly regarded loudspeakers measured surprisingly ragged anechoic responses in the 1960s
• Highly trained listeners can repeat subjective judgments with remarkable consistency
• Historical loudspeaker measurements were non-standardized and largely kept from the public
• Historically, published loudspeaker specifications were often artistic rather than factual.
• Home and headphone listening lacks the scientific research its prevalence warrants
• Home listening rooms show RT of 0.2–0.4 seconds with no diffuse field
• Home recording democratization raises demand for quality monitoring in untreated rooms.
• Home theater center channels are often inferior despite being the most important speaker
• Home theater centers must acoustically match L and R speakers lacking cinematic identical units
• Home theater owners routinely reduce volume by 10 dB or more
• Home theater RT targets demand costly low-frequency absorbers yet ignore the resonance problem.
• Home-room ‘reverberation time’ actually measures reflection or resonance decay
• Horizontal and vertical reflections dominate because they are the strongest first reflections.
• Horizontal localization is most acute straight ahead and degrades sharply to the sides.
• Horizontal localization uses binaural cues while vertical localization does not
• Horizontal-plane localization is mature while elevation reproduction is newly addressed
• HRTFs are measured in anechoic space as angle-dependent transfer functions
• HRTFs encode direction through head, ear, and torso shape filtering
• Human hearing normalizes wildly different acoustic environments to a constant source
• Human listeners can identify loudspeaker qualities through rooms, while microphones cannot.
• Human sound-quality judgments are skewed by expectation biases, not just the sound itself.
• Humans are least sensitive to delayed sounds emerging from the same speaker
• Humans can perceptually separate a sound source from its room.
• Humans detect spectral tilts as small as 1 dB across the audible range
• Humans hear spectral content, not waveform shape or phase shifts
• Humans normalize individual HRTFs from birth to recognize neutral timbre
• Humans perceive extended sound sources poorly when their parts emit identical tones
• Ignoring resonance Q can under-predict listener dislike of specific headphones
• Immersive music masters have no stable target playback format.
• Immersive systems could cheaply implement room reverb enhancement but none do.
• Impulse response measurements can misrepresent what listeners actually hear
• In rooms the inverse-square law applies only to the direct sound
• In small rooms reflections arrive early and never form a diffuse field
• In small rooms RT target 0.2-0.5 s; early reflections dominate mid-high frequencies
• In-ear drum reference point measurements are rarely performed due to invasiveness and unreliability.
• In-ear headphone performance data is scarce due to measurement challenges.
• In-ear headphones produce the most 4 kHz hearing loss among headphone types
• In-head localization stems from mismatched HRTFs and missing head tracking
• In-head sound localization may originate as a defensive response to ambiguous sources
• In-room measurement curves are dominated by reflections, not direct sound
• Independent large-venue preference studies across 47 years converge on the same target curve
• Individualized elevation cue perception makes listener-specific calibration permanent.
• Individualized HRTF data is required for reliable crosstalk cancellation
• Industry rivals codified Harman’s research into a formal loudspeaker measurement standard
• Industry-internal sound translation may be arbitrary but public translation cannot be
• Influential early analysis found truncated line sources have little to recommend them
• Inner ear hair cell damage accumulates before any measurable hearing threshold rise
• Inner-ear damage permanently corrupts higher-level auditory perception, not just thresholds
• Instantaneous switching between looped program excerpts yields more revealing audio evaluations.
• Instrument radiation patterns vary by frequency, shaping both stage reflection and audience blend
• Internet audio reviews lack bias control and thus unreliable evidence
• Interpreting mid-tier loudspeaker measurements is harder than spotting extremes
• Inverted signals cancel at all frequencies while delayed signals cancel selectively by frequency
• ITU and EBU listening tests differ fundamentally as relative versus absolute judgments.
• Knowing any two of room dimensions, subwoofer layout, and seating enables optimizing the third.
• Knowing product identity biases listening judgments through the placebo effect
• Lack of head-tracking dynamic cues causes headphone audio to sound internalized
• LARES enhancement was imperceptible during music but obvious during pauses.
• Large cone diaphragms develop breakup resonances at high frequencies that color sound
• Large diverse datasets of human HRTF and ear geometry are now being collected
• Large radiating surfaces become highly directional at high frequencies
• Large reverberant venues may compromise listeners’ ability to discern timbral qualities
• Larger recorded spaces perceptually dominate smaller playback spaces
• Late-arriving reflections within the fusion zone are audible but merge into one directional image
• Later-arriving reflections within the fusion zone do not create separate images.
• Lateral reflections near 60 degrees matter while front-rear reflections do little.
• Lateral sounds drive spatial perception more than frontal or rear sounds
• Lateral wall reflections arrive attenuated by inverse-square law distances
• Leakage-dependent bass makes closed-back headphone sound quality vary across listeners
• Leaks from hair, glasses, and jaw contours cause bass loss test fixtures miss
• Leaving the first side wall reflective reveals off-axis loudspeaker behavior in tests
• Line sources need listeners in the near field to keep their −3 dB falloff
• Listener ‘clarity’ ratings correlate with intelligibility but are not a direct measure
• Listener expectations, not acoustic cues alone, drive perceived spatial location.
• Listener expertise and gender shape rating patterns in loudspeaker evaluations.
• Listener fatigue objections can be answered by self-paced switch testing
• Listener judgment reliability declines with age and accumulated noise exposure
• Listener perception depends on sound power, direct sound, and reflections by frequency band
• Listener preference is driven mostly by timbral neutrality across the listening window
• Listener preference tolerances on headphone frequency response are narrowest through midrange
• Listener preferences correlate visually with smooth, flat anechoic on- and off-axis response.
• Listener preferences for neutral loudspeakers proved stable across decades and countries.
• Listener segmentation analysis can predict headphone preference from demographics
• Listener training improves performance plateau after only four sessions.
• Listener training targets resonance detection, not specific tonal preferences
• Listener-level channels, not height channels, drive spaciousness and envelopment
• Listener-preferred headphone response mirrors a neutral loudspeaker’s in-room response
• Listeners adapt to flawed speakers yet recognize superior ones
• Listeners adapt to loudspeaker flaws and still enjoy reproduced sound
• Listeners adapt to reverberant rooms within seconds, improving speech intelligibility by 18%
• Listeners adapt within minutes to externalize sound even through crude transducer devices
• Listeners are forgiving of headphone resonances but sensitive to bass-level air leaks.
• Listeners attribute bass imbalance to venues, not instruments, via auditory scene analysis.
• Listeners can distinguish loudspeaker resonances from instrument resonances
• Listeners can indicate preferred levels of individual reflected sounds
• Listeners can perceptually separate loudspeaker timbre from room coloration in comparisons
• Listeners cannot hear modal ringing below about 100 Hz once amplitude is equalized
• Listeners continuously re-normalize distorted HRTFs using visual and motion cues
• Listeners elaborate on flaws but give short praise to good products
• Listeners habituate to reproduced-sound faults without comparison listening
• Listeners judge loudspeakers equally well on studio-produced popular music
• Listeners judge reproduced sound against accumulated experience of live sound
• Listeners largely agree on preference, and preferred speakers measure smoothest
• Listeners must sit at least three wavelengths from diffusers to avoid coloration
• Listeners need some room sound but its required amount is unknown
• Listeners normalize room acoustics so a voice stays constant across radically different spaces
• Listeners over 55 prefer brighter headphones, possibly from age-related hearing loss
• Listeners perceive bass improvements primarily through reduced spectral bumps, not faster decay
• Listeners perceive the larger of two superimposed spaces in sound reproduction.
• Listeners perceive the pitch of a bass note even when its fundamental is absent.
• Listeners perceptually normalize familiar rooms to judge loudspeakers clearly
• Listeners perceptually normalize their own idiosyncratic HRTFs from birth
• Listeners perceptually normalize voices across changing room acoustics via direct sound and visual cues
• Listeners prefer excessive, even colored bass over deficient bass
• Listeners prefer familiar distorted phantom images over technically superior real center channels
• Listeners prefer flat amplitude response but are insensitive to phase shift
• Listeners prefer reverberation times of 1-1.1 s for piano in living-room-sized spaces
• Listeners rate neutral, uncolored reproduction as best, preferring it to any coloration.
• Listeners respond to resonance spectral prominence, not decay rate reduction
• Listeners strongly prefer the Harman target over DF, Lorho, and FF headphone targets
• Listeners tolerate second images in music because spaciousness outweighs them.
• Listening in large reverberant venues may compromise discernible sound qualities
• Listening seats placed near rear walls create early strong reflections that degrade imaging
• Listening window averaging estimates the direct sound heard by a typical audience
• Live concerts of big-name artists seek to reproduce recorded studio sound
• Live-versus-reproduced demonstrations were contrived marketing that flattered flawed loudspeakers
• Live-versus-reproduced demos were contrived marketing that masked genuine loudspeaker flaws.
• Liveness, not purity, is essential to natural-sounding music
• Loud bass masking spreads upward to cover the voice frequency range
• Loud bass masks sounds across much of the audible spectrum, including vocals.
• Loud hobbies may drive people to ever-louder home theater listening.
• Loud movie mixes get turned down, dragging dialogue below intelligibility
• Loud music damages cochlear structures in distinct ways producing distinct perceptual deficits
• Louder sounds are perceived as having more bass and bias subjective comparisons.
• Loudness compensation reduces effectively to a bass tone control
• Loudness curves from anechoic pure tones fail on real broadband program material
• Loudness depends on frequency, angle, duration, and envelope, not just level
• Loudness perception is robust enough that precise weighting matters little in practice.
• Loudspeaker angular separation, not rear placement, drives spatial immersion
• Loudspeaker design targets are set by human listeners, not engineering metrics
• Loudspeaker diaphragms support distributed resonances beyond lumped-element models
• Loudspeaker directivity and early reflections affect sound quality and imaging
• Loudspeaker directivity determines which curve predicts the room
• Loudspeaker evaluation must be done in mono because multichannel adds forgiveness
• Loudspeaker evaluation requires mono, while enjoyment happens in multichannel
• Loudspeaker off-axis response dominates in-room energy at the listening position.
• Loudspeaker quality depends on off-axis radiation because rooms reflect it
• Loudspeaker rated impedance figures are largely invented marketing numbers
• Loudspeaker resonances are the primary cause of poor sound quality.
• Loudspeaker voicing is a guessing game born of poor engineer-consumer communication
• Loudspeakers and headphones dominate perceived reproduced sound quality
• Loudspeakers and rooms act as a combined system that cannot be judged separately
• Loudspeakers and rooms function together as a single audible system
• Loudspeakers at high power and low frequencies become highly nonlinear.
• Loudspeakers do not break in but listeners adapt to new sound
• Loudspeakers without annoying resonances tend to adapt well in real-world listening.
• Low frequencies produce tactile whole-body sensation while higher frequencies drive pitch perception
• Low frequencies travel through structure walls and floors more than highs
• Low-frequency cutoff defined at −10 dB, not −3 dB, best predicts perceived fidelity.
• Low-frequency performance drives roughly 30 percent of sound quality ratings
• Low-frequency phase shift accumulates massively across every stage of the signal chain
• Low-frequency room resonances dominate how loudspeaker placement affects perceived quality.
• Low-frequency room resonances drive roughly 30 percent of perceived sound quality
• Low-frequency room response depends on woofer distances to floor and walls
• Low-Q resonance detection thresholds are remarkably low, making tonal changes easily audible.
• Low-Q resonances are most often excited by music and most audible
• Low-Q resonances become audible at peaks below 0.5 dB in the midrange
• Low-Q subwoofer resonances are audible mainly as spectral balance shifts
• Low, isolated axial modes dominate room problem-solving attention
• Lower Q spreads resonances wider in frequency but shortens time-domain ringing
• Lower-Q resonances are more audible than high-Q ones despite seeming better-damped
• Lower-than-reference listening levels require accessible bass tone controls for satisfaction.
• LP distortion is audible with test tones but masked by music.
• LP reproduction suffered hidden acoustical and resonance flaws beyond familiar noise
• LP tracing distortion arises because cutter and stylus follow different geometric paths
• Manufacturers resist publishing revealing measurement data because it would embarrass them.
• Many daily headphone users disbelieve headphones cause hearing damage despite symptoms
• Marketing fads can override objective engineering in product design
• Masked spectral components do not contribute to perceived timbre
• Master recordings must be evaluated in reflective rooms to translate to consumer listening
• Mastering engineers must undo sonic artifacts introduced by flawed mixing monitors.
• Mastering engineers often work in acoustically untreated domestic rooms.
• Matched room curves do not guarantee matching direct sound for imaging
• Matching acoustical and visual context yields convincing binaural externalization
• Matching room curves via EQ does not equalize audible sound quality.
• Matrixed quadraphonic crosstalk made localization unstable with head movement
• Matrixed quadraphonic downmixing produced crosstalk that shrank the listening position.
• Mean Output Level metric quantifies bass efficiency across seats
• Meaningful frequency-response specs require high resolution and narrow tolerance.
• Meaningful measurements have driven the industry toward timbral neutrality
• Measured data can challenge subjective impressions because conditions differ
• Measured interference at ear level often needs no correction
• Measurement accuracy on fixtures directly predicts agreement with human listeners
• Measurement axes produce low-frequency calibration errors from woofer offset and port placement
• Measurement research aims to map objective data onto subjective sound quality ratings
• Measuring power compression properly needs broadband program-like conditioning signals
• Mechanized positional substitution enabled fast double-blind loudspeaker product testing
• Microphone choice in recordings biases subjective loudspeaker ratings
• Microphone performance variation rivals or exceeds loudspeaker variation
• Microphone-array and panned recordings obey the same interchannel amplitude and time rules.
• Mid-field listening includes room sound without needing to eliminate the listening space
• Mid-room seating is required for full surround envelopment
• Mild hearing loss makes trained listeners give inconsistent sound quality judgments
• Mini-reflections perceptually add up beyond what visual reflection analysis predicts
• Minimizing floor-reflection dips in measured curves produced no audible improvement
• Minimum-phase loudspeaker resonances are correctable with parametric equalization.
• Minimum-phase reasoning lets frequency responses alone reveal room resonance behavior.
• Mismatched left-right speakers may degrade stereo imaging more than room effects.
• Mixdown at loud levels makes tracks need bass boost at quiet levels
• Mixer-friendly dead rooms do not guarantee better-sounding recordings for listeners
• Mixing decisions are monitored through loudspeakers in a room.
• Mixing engineers hear recorded sounds normal listeners will not perceive
• Mixing in acoustically dead rooms complicates translation to lively home listening
• Modal decay times below 80 Hz are achievable with parametric equalization
• Modal frequency resonance is position-independent while coupling is position-dependent
• Mode cancellation neutralizes modes for the listening system but not the physical room
• Modern crossovers no longer produce audible artifacts, defeating single-driver speaker advocates
• Modern immersive audio delivers perceptual clues rather than reconstructing real sound fields
• Modern insert headphones can limit output and measure hearing thresholds
• Modern loudspeaker differences are often statistical ties decided by program material.
• Modern loudspeakers converge so closely that choices become statistical ties
• Modern loudspeakers have converged so far that choice among them is statistically a tie.
• Modern studio mics are neutral transducers, while live mics trade neutrality for durability
• Monaural reproduction conveys reverberation only as a time-domain effect without spatial envelopment
• Monitoring through a colored loudspeaker embeds its signature into the recording
• Mono listening produces stronger and more consistent loudspeaker quality opinions than stereo
• Mono listening reveals a loudspeaker’s true character before stereo demo
• Monophonic listening is the most demanding test of loudspeaker sound quality
• More playback channels increasingly mask audible loudspeaker resonances
• Most amplifiers drive 4-ohm minima though low-impedance loads trigger limiting
• Most commercial Atmos music mixes are embellished stereo rather than true multichannel.
• Most commercial diffusers are designed for looks rather than measurable acoustic performance
• Most listeners can recognize audio excellence when comparing loudspeakers side by side.
• Most loudspeaker reviews rely on sighted listening susceptible to bias
• Most loudspeaker-wire mythology has no physical basis
• Most loudspeakers need equalization to correct low-frequency room resonances
• Most popular-music recordings are built from close-miked or synthesized sounds, not live acoustic performances
• Most recordings are abstract constructions, not accurate reproductions of live music.
• Most recordings are manipulated creations rather than live replicas
• Most reproduced program content is effectively monophonic
• Most US music is now produced in residential, acoustically poor rooms
• Movie and broadcast speech is poor material for revealing loudspeaker flaws.
• Movie center channels and multichannel music demand loudspeakers that perform well solo
• Movie sound designers keep on-screen sound centered and monophonic
• Movie sound mixers understand dialogue partly because they have rehearsed it
• Moviegoers tolerate poor sound because plot engagement dominates their enjoyment
• Movies are now more often viewed outside cinemas than inside them
• Movies reach audiences through many mismatched sound systems, breaking the calibration loop
• Moving a subwoofer away from a boundary toward a null reduces modal energy room-wide.
• MSV, MOL, and VSA are the formal metrics for evaluating multi-subwoofer bass.
• Multichannel and immersive audio reduce the perceptual importance of small-room reflections.
• Multichannel audio delivers directional reflections and long delays matching large venues
• Multichannel audio generates both localized off-screen sounds and convincing envelopment.
• Multichannel home theater benefits require delivering direct sound to all listeners in the room.
• Multichannel recording content masks room acoustics and loudspeaker resonances
• Multichannel reproduction progressively masks loudspeaker resonances except low-Q ones.
• Multichannel spaciousness requires bypassing inverse-square-law propagation loss
• Multichannel spatial information masks loudspeaker coloration in playback
• Multiple identical subwoofers reduce seat-to-seat bass variation
• Multiple independently-processed subwoofers tame room resonances for wider listening areas.
• Multiple listeners off the sweet spot need extra channels for envelopment.
• Multiple listening positions must be rotated to average out room bass variations.
• Multiple optimized subwoofers let a single global EQ filter flatten bass for every listener.
• Multiple subwoofers allow cheaper units at positions needing reduced drive
• Multiple subwoofers can replace bass traps and even improve efficiency
• Music benefits from dedicated side channels at ±60 degrees
• Music favors longer RT near 0.5 s while movies prefer 0.2 s
• Music industry resisted multichannel audio for cost reasons at every stage
• Music listeners prefer reflections far stronger and later than small rooms provide.
• Music’s dense spectrum masks its own distortion products.
• Musical note duration flattens reflection thresholds much like room reverberation does
• Musical program material flattens reflection threshold curves compared to speech
• Musicians do not reliably align with ordinary listeners in judgments
• Musicians judge loudspeakers on different rationales and can be inconsistent raters.
• Musicians make poor or unreliable subjective loudspeaker evaluators
• Musicians who are not audio enthusiasts judge loudspeakers on different rationales
• Naive and trained listeners agree closely on loudspeaker quality ratings
• Narrow-band tuned absorbers target specific modes while broadband traps address many
• Natural room reflections are too weak and early to please listeners of reproduced speech.
• Natural room reflections never exceed direct sound, so fusion never breaks down
• Natural room reflections never exceed direct sound, so precedence always holds
• NC contours rate noise but do not guarantee satisfactory spectral quality
• NC curves originated to rate speech intelligibility, not listener satisfaction
• Near field and far field mislabel room zones better called direct versus reflected-sound dominant
• Near-field listening exposes all of stereo’s array crosstalk colorations.
• Near-field listening removes room reflections that mask stereo colorations
• Near-field sound measurement is unreliable when multiple source parts radiate simultaneously
• Near-wall listening positions create early strong rear reflections
• Neural hearing damage occurs without measurable threshold elevation
• Neutral loudspeakers now exist but are not universally adopted in both domains.
• Neutral loudspeakers preserve musical inspiration better than colored ones
• Neutral loudspeakers should be transparent messengers of the art
• Neutral monitors are clear windows separating artist from mix.
• Neutral reproductions serve as a reliable baseline for tonal preferences
• No accepted method rates subjective acceptability of ambient noise spectra
• No reverberation-time formula has universal applicability across rooms
• No scientific evidence shows audible break-in changes except minor woofer low-bass compliance
• No single acoustic treatment satisfies because satisfaction is multidimensional
• No single ear-simulator correction applies because error is headphone-specific
• No single equalization target curve can suit all listeners
• No single headphone target satisfies most listeners
• No single loudness compensation curve can serve music with dynamic range
• No single loudness meter can capture subjective loudness of varying program material across environments
• No time-frequency analysis method has psychoacoustic validation for room decay.
• No universal sound-quality model exists; listener data is the only shared starting point
• Noise-cancelling headphones now deliver up to 30 dB of isolation
• Non-auditory factors strongly bias loudspeaker purchase preferences in sighted listening
• Non-linear distortion generates new frequencies as level-dependent behavior shifts.
• Non-parallel walls do not eliminate room modes
• Nonlinear distortion adds frequencies that were not in the original signal
• Nonlinear distortion generates new frequencies that change timbre with volume
• Nonlinear vibration generates new frequencies absent from the original stimulus
• Normal listening rooms improve rather than impair speech intelligibility
• Notching a room mode reduces woofer distortion and lets louder playback
• Object-based audio sacrifices sound quality but suits transient effects; fixed images suit music.
• Objectionable room perceptions are unlikely to stem from comb filtering
• Objective measurements routinely expose flaws that subjective listening reviews miss
• Oblique speaker placement pushes problem reflections into heavily attenuated off-axis angles
• Occupational hearing guidelines allow damage, not prevention of loss.
• Occupational hearing guidelines permit hearing loss rather than prevent it
• Occupational hearing-conservation guidelines fail to protect audio engineers’ ears
• Occupational noise limits fail to protect recreational hearing enjoyment
• Occupational noise standards accept measurable hearing loss and do not protect critical listening
• Off-axis measurement data was recognized as valuable from early analog systems
• Off-center listeners lose the phantom center image which collapses toward the nearer loudspeaker
• Off-center listeners lose the stereo illusion but retain musical content
• On-axis curves alone cannot predict loudspeaker sound quality
• On-axis flatness alone fails without controlled off-axis directivity.
• On-axis flatness and smooth off-axis response predict 75% of listening preference
• On-axis frequency response cannot predict in-room measurements but does predict perceived sound.
• On-axis response alone cannot predict how a loudspeaker sounds in a room
• Only sound quality and spatial effects can be physically controlled in recordings
• Open-back headphones deliver the most consistent response across listeners.
• Open-back headphones give consistent bass response across listeners because fit does not affect it.
• Open-ear headphones lack bass and tempt users to raise volume against background noise
• Operators lowering volume to fix loudness harms speech intelligibility
• Opposing in-phase subwoofers cancel odd-order axial modes but amplify even-order ones.
• Opposite-polarity subwoofers can null a specific room mode’s coupling
• Opposite-wall reflections compensate for surround propagation loss at no cost
• Optimal room ratios as originally conceived are irrelevant to sound reproduction
• Optimal woofer placement makes boundary distances as different and non-multiple as possible
• Optimized multi-sub systems can use much smaller subs at some locations
• Optimized room-dimension ratios may not reliably produce better-sounding rooms.
• Optimizing any two of room, subwoofer, and seating yields the third
• Overhead violin miking captures a strident 2500-5000 Hz beam requiring equalization.
• Paired comparisons demand six times more trials than multiple comparisons for four loudspeakers.
• Panel loudspeakers’ low-mass diaphragms do not actually respond faster than conventional coils
• Panel movement alone does not indicate audibly radiated sound.
• Panel vibration does not prove audible sound is radiated
• Parametric equalization of minimum-phase resonances also reduces time-domain ringing
• Perceived break-in effects stem from listener adaptation, not product change
• Perceived loudspeaker sound quality depends only on amplitude responses
• Perceived quality is judged as deviation from an ideal amount.
• Perceived spaciousness scales with playback level because faint reflected sounds must be audible
• Perceived spectral balance matches on-axis response more than sound power or room curve
• Percentage distortion metrics include inaudible masked components and mispredict perceived quality
• Perceptual changes detected at threshold become desirable when heard as image broadening
• Perceptual listening-through-room ability has finite limits
• Perceptual masking hides large LP distortions that measurements reveal
• Perfect diffusion is an unattainable ideal in real rooms
• Perfect HRTF matching does not guarantee better headphone sound quality
• Personalized HRTFs enable elevated externalized spatial audio over headphones
• Personalized HRTFs improve sound externalization in binaural reproduction
• Phantom center dullness stems from destructive acoustical interference, not loudspeaker inadequacy
• Phantom center image sound quality is inherently compromised even in the sweet spot
• Phantom center images reduce speech intelligibility due to interaural crosstalk
• Phantom imaging lets object-based audio create many locations from few loudspeakers
• Phantom stereo images resist lateral-reflection interference as well as real images do
• Phase response stops being audible once sound leaves the loudspeaker
• Phase shift is largely inaudible for reproduced music in reflective rooms
• Phonograph playback added high percentage distortion that stayed inaudible under music
• Physical headphone testing cannot be fully blinded because listeners feel weight and fit
• Physically separated MTM drivers acoustically interfere off-axis because both radiate overlapping high frequencies
• Piano timbre would be unstable if we heard phase changes.
• Pinna geometry alone changes headphone measurements through leakage
• Pinna, head, and torso shapes encode spatial direction into ear-canal sounds
• PIR predicts preference via smoothness cues, not the room curve itself
• Plausibility and expectation drive perceived vertical localization more than physical cues
• Playback in noisy environments is shrinking audio dynamic range.
• Point-source mic capture loses the binaural ability to separate direct from reflected sound
• Polarity reversal and electronic decorrelation fixed mono surround head-localization.
• Positional equalization finds seating spots weakly coupled to resonances
• Powered subwoofer hardware can be repurposed as active bass absorbers
• Practical diffusers need depth set by wavelength of the lowest frequency treated
• Pre-distortion compensation failed because tracing distortion varies with stylus shape
• Precedence accumulates source information while late arrivals actively disrupt perception
• Precedence effect threshold curves hold stable across very different listening environments
• Precedence fusion is not masking; all reflections remain audible
• Precedence fusion suppresses spatial perception but never masks the delayed sound
• Predicting preference is easier for in-ear than over-ear headphones
• Predicting subjective listening preference from measured data remains a hard unsolved problem.
• Predicting subjective loudspeaker preference from measurements was long considered impossible
• Preference bounds, not a single target, statistically satisfy most headphone tastes
• Preference models trained on homogeneous product sets may not generalize
• Preferred headphone tone adjustments depend on music program and listener attributes
• Preferred large-venue room curves converged across 47 years of independent experiments.
• Preferred piano reverberation exceeds what furnished rooms naturally produce
• Preferred treble level rises 3 dB per decade of age over 30
• Preferred TV and film dialog playback levels vary widely across listeners.
• Price predicts output and looks, not basic sound accuracy
• Processing corrected at discrete seats also improves sound between and around those seats.
• Professional control room designs range from dead to highly diffuse.
• Professional monitor loudspeakers were not reliably neutral or accurate references of sound quality
• Professional monitors rated lower than consumer products in blind sound quality tests.
• Program material and recording quality strongly determine audibility of speaker defects
• Program material choice determines which loudspeaker or room flaws get revealed
• ProLogic’s flaws came from design for film, not home music
• Psychoacoustic loudness models cannot accurately predict individual listener responses
• Published loudspeaker impedance ratings rarely represent actual frequency response
• Published spinorama measurements frequently violate standard resolution requirements and are then unreliable
• Pure diffuse-field calibration yields inadequate bass and low preference ratings
• Quadraphonic audio failed partly from lacking a psychoacoustic foundation.
• Quadraphonic forced vinyl playback bandwidth to 50 kHz, improving LP quality
• Radiation directivity depends on wavelength relative to source size
• Raising volume to overcome noise leads to discomfort and hearing damage
• Random loudspeaker repositioning across listening seats eliminates room-position bias
• Random-incidence absorption coefficients fail to predict actual reflected spectra
• Randomizing identifiers, positions, and music prevents experimenter bias in listening tests
• Randomizing lateral speaker positions averages out width-mode influences in tests
• Randomizing positions and identifiers cancels room standing-wave biases in double-blind tests
• Randomizing speaker locations is needed to average out room effects.
• Randomly spaced hemi-cylinder diffusers work far better than contiguously placed ones
• Real listening rooms produce semi-reflective fields, not free or diffuse fields
• Real reflections are attenuated enough to tame comb filtering drastically
• Real-room reflections are attenuated and delayed, not equal-level and immediate.
• Realistic noise reduction measures require soundscape recordings rather than pink noise.
• Rear-boundary reflections add decorrelated sound that degrades imaging and soundstage
• Receiver bass-management implementations vary, causing differing user experiences.
• Recognizing reproduced-sound deficiencies is a universal skill independent of taste
• Recommended playback levels are often higher than what listeners actually prefer.
• Record label tape-erasure practices corrupted early CD releases at the source
• Recorded art translation depends on a shared consumer-professional audio standard
• Recorded room ambience may distract listeners from evaluating raw loudspeaker quality
• Recorded spatial content, not loudspeakers, dominates stereo perception
• Recording complexity and reverberation raise the audible threshold for resonances
• Recording engineers preferred direct-sound fields partly to mask poor monitor loudspeakers.
• Recording monitors with deliberate response errors perpetuate the circle of confusion
• Recording room acoustic variations cause the circle of confusion
• Recording studio background noise should approach the hearing threshold
• Recording technique is the prime determinant of spatial impressions in sound reproduction
• Recordings are artistic constructions, not literal captures of live sound
• Recordings are artistic creations, with loudspeakers merely the messengers.
• Recordings translate because recording processes add none of the defects listeners reject.
• Recordings with broadband spectral variations still reliably reveal loudspeaker resonances
• Records capture hall reverberation, so home rooms need not add any
• Recovered hearing thresholds can mask permanent neural damage
• Recreational gunfire is the most serious recreational threat to hearing
• Rectangular rooms allow predicting low-frequency modal behavior in advance
• Rectangular rooms are favored because their modes are simply computable
• Rectangular rooms are preferred because their modes are predictable
• Reducing energy in a single problem mode lowers seat-to-seat response variance.
• Reflected sound anchors external source localization while its absence pulls sound into the head
• Reflected sound fields cannot be corrected by electronic equalization alone
• Reflected sound fields dominate at low frequencies for almost all sources
• Reflected sounds physically dominate what reaches listeners’ ears
• Reflection control reduces reflected energy either by absorption or by scattering.
• Reflections arriving from about 50-70 degrees lateral maximize perceived spaciousness.
• Reflections from adjacent walls create destructive interference nulls at one-half wavelength spacing.
• Reflections increase sensitivity to low and mid-Q resonances in reproduced sound
• Reflections that appear as destructive comb filtering actually create perceived spaciousness.
• Relaxed room-standard requirements eroded the comparability that motivated them
• Reliable panel listeners show low variance and wide rating ranges
• Reliable subjective ratings are prerequisites for validating technical measurements
• Removing floor reflections makes sound unnatural to human listeners
• Renderers use metadata to adapt recordings to any loudspeaker configuration.
• Repeated familiar program excerpts make the most effective listening-test stimuli.
• Repeated loud exposures convert temporary hearing loss into permanent damage
• Repositioning woofers near the rotation axis improves low-frequency measurement splicing accuracy
• Reproduced recordings can reveal high-frequency detail inaudible in live concert halls
• Reproducing the live venue experience has been the longstanding goal of audio enthusiasts
• Resistive absorbers are impractical at low frequencies because quarter-wavelengths are huge
• Resistive absorbers only work where air particles move, which pushes them to high frequencies
• Resonance detection thresholds rise with higher Q and lower frequency
• Resonance Q factors below about 16 are subjectively imperceptible to listeners.
• Resonance Q reductions below about 16 are subjectively imperceptible
• Resonance-free response and flat direct sound define timbral neutrality
• Resonances are the primary problem in loudspeakers
• Resonances near anechoic thresholds become audible again in reflective rooms
• Resonant peaks bother more listeners than nulls because they occupy most of the room
• Respected researchers disagree on optimal room ratios, undermining confidence in the concept.
• Responsible listening tests use discriminant-selected programs and within-program comparisons
• Reused master tapes corrupted early CDs, explaining poor CD-versus-LP comparisons
• Reverberation enhancement can transform a home theater into a concert hall seamlessly
• Reverberation extends the fusion zone in which reflections merge with the direct sound
• Reverberation masks high-Q ringing but amplifies low-Q resonances
• Reversible threshold shifts after noise exposure mask ongoing neural degeneration
• Reviewers often conflate the room and program with the loudspeaker’s own sound
• Reviewers with trustworthy anechoic data produce far more reliable opinions
• Room acoustical behavior changes across a broad transition region, not at one frequency
• Room acoustics and presentation method alter how listeners perceive sounds
• Room acoustics dominate perceived bass response below roughly 250 Hz
• Room acoustics matter progressively less as channel count increases above Schroeder frequency.
• Room acoustics shift from standing waves to irregular interference as frequency rises
• Room acoustics were the one loudspeaker variable manufacturers could not control without EQ
• Room boundary reflections are the second loudest sounds a listener hears
• Room correction cannot substitute for two-eared timbral and spatial perception
• Room curve variations across control rooms distort recordings’ spectral balance
• Room curves are measurement results, not equalization targets, except at bass
• Room curves cannot define perceived sound quality on their own
• Room curves show loudspeaker results, not targets worth equalizing toward
• Room differences dominate loudspeaker differences when listeners cannot adapt
• Room diffusion is not required for perceived spaciousness
• Room effects minimally influence steady-state response above 1 kHz
• Room modes being minimum-phase means fixing the spectral bump also fixes the ringing
• Room pressurization creates a compliant bass boost below the first axial mode
• Room pressurization is a compliance effect that fades in unsealed rooms
• Room reflection effects are masked by spatial information already in recordings
• Room reflections aid resonance audibility that headphones must control internally
• Room reflections are essential; anechoic listening is deeply unpleasant
• Room reflections cannot be corrected by electronic equalization
• Room reflections improve rather than degrade sound-distance estimation accuracy
• Room reflections improve the ear’s ability to hear resonances in playback.
• Room reflections mitigate the phantom-center comb-filter dip near 2 kHz.
• Room reflections partially fill the phantom-center spectral hole
• Room reflectivity at low frequencies determines bass elevation in measured steady-state curves
• Room resonance excess masks loudspeaker bass deficiency to listeners
• Room resonances are minimum-phase and yield to frequency equalization
• Room response at a listener can be predicted from geometric reflection analysis
• Room reverberation barely affects early reflection audibility but strongly elevates late-reflection thresholds
• Room size and shape do not change multiple-loudspeaker sound quality ratings
• Room size does not alter steady-state curves above 400 Hz
• Room standing waves dominate below the Schroeder frequency while the loudspeaker controls above it
• Room standing waves mask the adjacent-boundary effect even after averaging.
• Room treatment absorbers receive sound at 45 to 60 degrees incidence
• Room-acoustics research transfers poorly because listening rooms have known source and receiver positions.
• Room-ratio research assumed unknown source locations unlike reproduction’s fixed positions
• Room-treatment marketing outpaces rigorous subjective testing
• Rooms shift absolute ratings but not loudspeaker rankings in multiple-loudspeaker comparisons
• Roughly 75 percent of people have sufficiently normal hearing to make reliable loudspeaker judgments
• Science cannot measure the aesthetic qualities that make music revered
• Screen fabric must lose under one dB yet remain porous enough to conceal speakers
• Screen fabric transparency requires tension and verification under 1 dB
• Seal leakage makes closed-back headphone bass highly listener-dependent.
• Seat effects are perceptually insignificant and skip equalization
• Seat position changes coupling to standing-wave nulls and peaks
• Seat-caused acoustical interference eludes equalization and often goes unnoticed by listeners
• Seating that avoids low-order null lines reduces seat-to-seat variation
• Seats placed on room-mode null lines increase seat-to-seat bass variation.
• Seeing a known loudspeaker erases sensitivity to room-position changes
• Seeing the loudspeakers during evaluation actively stresses trained listeners
• Selecting flattering monitors perpetuates the flaws of earlier generations.
• Shoebox-shaped concert halls naturally produce abundant lateral reflections
• Side-placed surround speakers beat rear placement by wide margins
• Side-positioned surround loudspeakers are preferred over rear placement, known since 1971
• Side-wall reflections aid spatial impression while front and rear early reflections do little
• Sighted evaluations of acoustical rooms are biased by visual distinctiveness
• Sighted evaluations stress trained listeners who no longer accept visual bias.
• Sighted listeners become ‘deaf’ to program-dependent sound differences
• Sighted listeners ignore program differences that blind listeners react to
• Sighted listeners recall prior ratings and ignore audible position differences
• Sighted listening evaluations are biased regardless of listener expertise
• Sighted loudspeaker evaluations are contaminated by non-auditory visual and social cues
• Sighted loudspeaker evaluations are demonstrably unreliable
• Sighted reviewer claims about cables contradict controlled measurements
• Signal synthesis enabled creative experimental tests of hearing.
• Signal-adaptive matrix steering works only for single moving images
• Silence intervals of half a second to a second aid auditory discrimination accuracy
• Simple loudness-compensation bass boosts cannot work for dynamic-range music
• Simultaneous subwoofer outputs cannot be predicted from individually measured responses
• Single-axis measurements misrepresent multidirectional loudspeakers like Bose
• Single-number loudspeaker ratings mislead because real faults often have straightforward corrections
• Single-stimulus listening relies on capricious long-term memory and yields contradictory opinions
• Sitting close to a rear wall creates early strong reflections that corrupt perceived sound
• Six or more equally spaced speakers imitate a diffuse array well; four do not
• Slightly mis-tuned parametric filters still effectively attenuate targeted room modes
• Small listening rooms lack diffuse reverberation and contain only early reflections
• Small playback rooms impose their own early reflections on recorded sound
• Small-room acoustics constrain bass quality below the Schroeder transition frequency.
• Smaller drivers radiate more omnidirectionally at a wider frequency range
• Smaller rooms drastically worsen envelopment at off-center seats
• Smooth equalized room curves often signal degraded sound quality
• Smooth flat on- and off-axis response correlates with subjective preference.
• Smoother, flatter, wider-bandwidth on-axis curves predict higher subjective loudspeaker ratings.
• Soffit mounting in control rooms is a non-optimal corruption of half-space mounting
• Solo voice and simple instrument recordings least reveal loudspeaker flaws
• Some audible complaints are recording format flaws, not playback faults
• Some audiophile claims about playback components flout physical laws
• Some listeners reject headphones due to in-head localization and lack of bass tactility
• Some professional monitors have resonance and directivity flaws no equalization can fix
• Sound angled into absorbers absorbs more by traveling through more material
• Sound field complexity does not change resonance detection thresholds
• Sound Field Management handles flexible subwoofer placement in irregular room shapes
• Sound localization by elevation is guided by plausibility, not just acoustics
• Sound power alone cannot predict listener preference for loudspeakers
• Sound power alone does not predict loudspeaker sound quality.
• Sound power calculation mitigates low-frequency calibration errors from woofer displacement
• Sound power is a poor estimator of bass performance in real rooms.
• Sound power predicts room response for omnidirectional speakers while directivity shapes room curves
• Sound quality is judged as deviations from ideal amounts of perceptual dimensions
• Sound reflecting off a hard boundary has zero particle velocity
• Sound reproduction quality depends on both physical acoustics and human perception
• Sound wave molecules have zero velocity at compression peaks due to inertia
• Sound-power specifications only make sense in diffuse fields impossible in small rooms
• Source and receiver placement effects on modes occur at all frequencies
• Spaciousness comes from natural room reflections, recorded multichannel reflections, or both.
• Spaciousness contributes equally to naturalness and dominates pleasantness perceptions
• Spaciousness dominates pleasantness more than sound quality does.
• Spatial averaging and in-situ power measurement reveal identical boundary effects
• Spatial averaging of measurements suppresses interference artifacts while preserving spectral information
• Spatial averaging reveals boundary effects hidden by standing waves
• Spatial envelopment requires uncorrelated ear signals, not a diffuse sound field
• Spatial low bass below 50-63 Hz has an audible directional cutoff
• Spatial richness in multichannel sound inhibits perception of loudspeaker resonances
• Spatial-averaged measurement curves reveal real resonances through shared bumps.
• Spatially averaged curve families reveal audible resonances hidden in single measurements
• Spatially averaged equalization can satisfy no individual listener
• Speaker break-in effects are listener adaptation, not hardware change
• Speaker cables and devices show near-zero audible differences in blind tests
• Speaker midrange errors can stem from resonant diaphragm flexure and be fixed by damping.
• Speaker specs like ±3 dB 80 Hz-18 kHz convey almost no useful information
• Speaker wire and cables show negligible audible differences under controlled tests
• Speaker wire resistance is negligible compared to tube amplifier output impedance
• Spectral balance errors predict headphone preference ratings independent of resonance Q
• Spectral variations inside one critical band alter perceived timbre
• Speech and solo instruments reveal loudspeaker flaws least, dense broadband music most
• Speech and solo voices are the least revealing test sounds for loudspeaker flaws
• Spinorama measurement grew out of loudspeaker-room interaction studies
• Staggering absorption zones on facing walls suppresses flutter echoes in listening rooms.
• Standard octave-band smoothing hides the fine structure of comb-filter patterns.
• Standard studio calibration levels are measurably too loud for typical listeners
• Standing versus seated position changes perceived sound quality only insignificantly
• Standing waves create loudness dips at room midpoints
• Standing waves form when wavelengths match room dimensions
• Standing-wave thinking applies only at low frequencies in small rooms
• Statistical acoustics and classical critical distance do not apply in small rooms
• Statistically confirmed listener preference for neutral timbre with deep bass
• Steady-state comb-filter measurements fail to represent how transient sounds are heard
• Steady-state frequency curves misrepresent how transient music interacts with reflections.
• Steady-state frequency response is the reliable indicator of audible room resonances
• Steady-state room curves above 400-500 Hz misrepresent perceived sound quality.
• Stereo and multichannel listening make listeners more forgiving of loudspeaker flaws
• Stereo hearing exploits only one directional cue and the ear fills in the rest
• Stereo phantom center images have a spectrum dip near 2 kHz from interaural crosstalk
• Stereo phantom images timbrally differ from real-source or mono center images.
• Stereo playback masks differences between loudspeakers with room reflections
• Stereo presentation masks audible differences between loudspeakers found in mono.
• Stereo principles were understood by 1931 but waited decades for commercialization.
• Stereo recordings strip away the delayed sounds essential to live music
• Stereo reproduction is an experimental basis, not a fixed system
• Stereo upmixing quality varies because it depends on the pairing of recording and upmixer.
• Stereo won commercially because LP grooves could only store two channels
• Stereo’s dominance stemmed from LP storage limits, not audio ideals
• Streaming loudness normalization is automating much of mastering engineering.
• Streaming services vary so much in level that volume settings mislead listeners.
• Strong direct sound without supporting reflections causes in-head localization in loudspeaker listening
• Sub-2-ohm speaker designs caused the amplifier differences reviewers praised
• Subjective agreement requires identical delivered signals and matched objective measurements
• Subjective audio opinions can behave like facts when gathered under controlled conditions
• Subjective experience dictates which measurements matter in audio research
• Subjective judgment remains the ultimate reference for loudness measurement schemes
• Subjective listening opinions shift with time and new information
• Subjective listening remains the final authority over measurement validity.
• Subjective listening tests require repetition and randomization to be statistically valid
• Subjective rating scales stretch elastically as stimulus range narrows
• Subjective sound quality is authoritative and measurements must explain it
• Subwoofer arrays can be time-aligned and equalized to minimize seat-to-seat bass variation
• Subwoofer mode cancellation needs no equalization to fix boom
• Subwoofer placement conclusions were validated across many room dimensions.
• Subwoofer placement itself can be optimized alongside DSP settings
• Subwoofer placement severely impacts the electrical power needed for equal low-bass output.
• Subwoofer time-domain speed is set by amplitude response, not driver design
• Subwoofers aid rather than harm good sound reproduction
• Subwoofers must be equalized together, not individually, to sound right
• Subwoofers radiate omnidirectionally because their wavelengths far exceed diaphragm size
• Surface wall mounting creates a comb-filter cancellation at the woofer-to-wall round-trip wavelength
• Surround loudspeakers close to listeners become distractingly localizable.
• T30 and T20 measure RT by extrapolation and assume linear decay
• Tactile seat vibration substitutes for about 3 dB of headphone bass.
• Tall speakers with stacked woofers are not true line arrays
• Technical audio decisions need measurement science separate from artistic opinion
• Technical measurement is necessary for subjective audio judgments to be meaningful.
• Test fixture fidelity to human measurements remains an open question
• Test fixtures meeting the same standard still differ in headphone measurements.
• Testing real human panels for anatomical representativeness is impractical, driving manikin approaches
• The ‘we can’t measure what we hear’ myth stems from inadequate measurements
• The 30 ms fusion limit applies only to equal-level speech in hemi-anechoic space
• The audio industry still lacks a scientific foundation for format decisions
• The Auratone 5C reference speaker was objectively poor and inconsistent across samples
• The breakdown of precedence yields a subordinate second image, not equal images.
• The cancellation dip shifts to higher frequencies and weakens as measurement moves off axis.
• The center channel carries most dialog and on-screen sound in movies
• The cinema ‘closed loop’ of sound translation has broken as viewing fragmented
• The cinema X curve standard was based on primitive measurements despite better published guidance
• The dipole surround era ended because it was not scientifically sound
• The direct, on-axis sound dominates perceived loudspeaker quality in rooms.
• The distinctive LP sound is an artifact, not fidelity to the master
• The ear’s sound-level-dependent nonlinearities cannot be substituted or corrected for
• The favored reflection conditions measure as comb filtering yet sound pleasing
• The first-arriving direct sound perceptually dominates despite carrying less energy
• The flat DF target fails listening tests mainly due to insufficient bass
• The Harman in-ear target remains top-ranked across independent validation studies
• The Harman target curve applies only below the transition frequency.
• The Harman target satisfies most listeners but bass preferences split by age and gender
• The hearing system adapts well to phantom stereo images despite conflicting HRTF cues
• The hearing system is not outmeasurable; inadequate measurements explain apparent gaps
• The ideal room ratio dogma originated from industrial reverberation chambers, not listening rooms
• The international standard DF target curve rates worse than alternatives
• The ITU loudness standard uses K-weighting with a 4 dB high-frequency head boost.
• The ITU-R BS.1116 standard is routinely misapplied to loudspeaker evaluation rooms.
• The knuckle test misjudges cabinets because contact excitation differs from internal pressure.
• The LFE channel was created to handle blockbuster bass beyond 40 Hz.
• The listening room, not the loudspeaker, determines perceived bass quality.
• The listening room’s influence is suppressed during multichannel playback
• The listening room’s influence on sound diminishes as channel count increases.
• The LP medium was fundamentally incapable of reproducing master tape sound
• The null of the phantom-center comb filter makes the sweet spot findable by ear
• The open sound of open-back headphones may just be room acoustics leaking in.
• The optimum direct-to-reflected sound ratio rises from speech to music
• The original Schroeder constant fits small rooms better than the revised one
• The phantom center image in stereo is always corrupted at the symmetrical sweet spot
• The phon unit measures perceived loudness, not physical sound level
• The precedence effect fusion interval lengthens with signal continuity
• The precedence effect suppresses spatial identity of reflections, not their audibility
• The precedence-effect fusion interval in real rooms far exceeds laboratory values
• The preferred headphone EQ matches a 10 dB downward-sloped room response
• The preferred headphone EQ matches the loudspeaker’s predicted in-room response.
• The rigorously validated Harman target became the industry’s blind-listening benchmark
• The Schroeder frequency miscalculates for small furnished rooms but the transition is real
• The science of acoustics began with concert hall reverberation theory
• The spinorama is the default standard display for anechoic loudspeaker data.
• The steady-state room curve should tilt downward while the direct sound stays flat
• The stereo phantom center image suffers an audible 2kHz timbre dip affecting speech intelligibility
• The term spinorama derives from rotating the loudspeaker to gather response data
• The three listener classes differ mainly in preferred bass level
• The UREI 811B, a popular studio monitor, scored lowest in double-blind listening tests
• The variety of loudspeaker sounds in the marketplace originates from uncontrolled subjective evaluations
• The ventriloquism effect lets a single monophonic center channel satisfy most on-screen dialogue
• The X-curve target does not deliver the neutral direct sound it was believed to
• THX dipole surround speakers degraded direct sound while failing to create genuine diffusion.
• THX dipole surrounds were bidirectional out-of-phase pairs, not true dipoles
• THX-certified dipole surrounds varied wildly in measured sound quality
• THX-type dipole surrounds produced irregular mid-frequency depressions, not neutral nulls
• Timbral adaptation is a confirmed phenomenon though its mechanism remains unexplained
• Timbral neutrality drives 69.5 percent of sound-quality preference
• Time and frequency resolution cannot both be improved simultaneously
• Time-domain reflection displays conceal spectral content and mislead comparison
• Toe-in aimed at the listener compensates off-center phantom drift only at mid-to-high frequencies
• Toe-in aiming of front loudspeakers minimizes problematic side-wall reflections
• Toe-in loudspeaker aiming failed to stabilize phantom center imagery off-axis
• Tone controls are a rational fix for recording-to-recording spectral variation
• Tone controls remain essential because recordings and rooms vary widely
• Tone-control adjustments are easily heard because low-Q resonance thresholds are tiny
• Too much uncorrelated rear-wall diffusion scrambles center imaging
• Top-rated headphone responses cluster tightly around a shared mean curve.
• Total sound power is a spherical area-weighted sum over full orbitals around a speaker
• Traditional distortion specs fail to predict perceived sound quality
• Trained and untrained listeners mostly rank loudspeakers the same way
• Trained listeners can draw accurate spectral-balance curves of what they hear
• Trained listeners can verbally connect sound preference to measurable on-axis and listening-window curves
• Trained listeners perceive flat spectra from loudspeakers whose on-axis response is flat
• Transducer transient response is fully predictable from its amplitude response
• Transducers dominate perceived sound quality more than other chain components
• Treating a measured reflection can remove it while leaving its audible effect intact
• Treble boost in loudness controls damages sound quality unnecessarily
• True diffuse sound fields cannot form in small absorptive listening rooms
• True envelopment needs reflections delayed beyond 80 ms, impossible in small rooms alone
• True envelopment requires delayed signals that only multichannel playback can supply
• True envelopment requires delays beyond 80 ms that rooms cannot supply
• Tube amplifiers audibly color loudspeakers as those become more neutral
• Tube amplifiers sound different mainly because their high output impedance alters loudspeakers
• Turning down cinema volume to reduce loudness harms dialog intelligibility.
• Turntable movers cheaply enable blind loudspeaker testing for most use cases.
• Twenty headphone models were measured across five fixtures using 200 averaged measurements.
• Twenty-dollar in-ear headphones can outperform costly loudspeakers in fidelity
• Two subwoofers in opposite mode lobes can cancel room resonances without equalization
• Two-channel stereo only works for one centrally seated listener
• Unidentified or invisible sounds are perceived as coming from behind the head
• Unscientific voicing practices caused arbitrary variations in loudspeaker sound
• Unstandardized loudspeakers once meant recordings could not reliably reproduce their intended sound.
• Untrained listeners in method-of-adjustment tests prefer the boosted “happy face” spectrum.
• Untrained listeners reach quick, consistent sound-quality judgments when switching is instantaneous and sequence-blind.
• Updating a classic loudspeaker can yield more output yet worse tonal quality.
• Upmixer quality depends on matching parameters to the specific recording
• Upmixers extract ambience already in recordings, not synthesized reverb
• Upmixers that overuse the center channel degrade the stereo music soundstage.
• Upward masking makes intermodulation difference tones more audible than harmonics
• Vinyl’s own asymmetrical distortion confounded early polarity-audibility tests
• Virtual headphone testing cut switching time tenfold and improved rating consistency.
• Virtualized loudspeaker playback can compete with real multi-speaker systems on listener preference.
• Visual and contextual cues bias human judgments of sound quality
• Visual appearance of loudspeakers shifts listener preference ratings
• Visual gesticulation, not sound, dominates judgments of musical performance
• Visual-vestibular room matching is required for binaural externalization to persist
• VR with synchronized binaural audio can deliver presence for live events
• Wall mounting creates a comb-filter cancellation dip whose frequency scales with baffle size.
• Wall projections must exceed one-seventh wavelength to scatter sound usefully
• Waterfall diagrams alone poorly estimate the audibility of resonances
• Waterfall display parameters can make a room look far worse than it is
• Waterfall measurements reveal no information beyond what frequency response curves provide.
• Waveform details are relatively unimportant to auditory perception
• Weighting-curve blind spots create incentive to over-boost bass
• Well-damped low-Q resonances are easier to hear than high-Q ones.
• Well-designed loudspeakers are recognized by ordinary customers only under valid comparison conditions
• Well-designed loudspeakers converge on neutral, nearly identical sound.
• Well-designed loudspeakers from 1980s rival today’s high-end products
• Wide-dispersion loudspeakers soften hard-panned images and reduce the center-image crosstalk dip
• Wide-dispersion loudspeakers with room reflections create a you-are-there listening perspective
• Wide-dispersion speakers plus room reflections create listener envelopment.
• Woofer excursion limits constrain dynamic range more than tweeter capabilities do