Only the octave stays perfectly in-tune in equal temperament

Related

• Equal temperament makes combination tones slightly out of tune (similarity 0.89)
• No keyboard tuning can make every key sound justly intonated (similarity 0.89)
• Tenors need not tune their tracts because their pitch-to-formant ratio stays high (similarity 0.86)
• Even steady-state musical notes vary in amplitude envelope over time. (similarity 0.85)
• Vibrato produces tremolo when harmonics sweep across resonant peaks (similarity 0.84)
• Flute playing frequencies are impedance minima; trumpet’s are maxima (similarity 0.84)
• Equal temperament tuning relies on learned memory with no physical beating guide (similarity 0.83)
• A capella groups can adopt just intonation, causing overall pitch to drift through keys (similarity 0.83)
• A pianoforte with raised dampers can physically re-echo sung vowels via sympathetic resonance (similarity 0.82)
• Musical scales universally favor intervals with small integer frequency ratios (similarity 0.82)
• A strictly periodic tone can still be perceived as two distinct notes (similarity 0.82)
• Hard reeds fix pitch, freeing resonators to shape only harmonics (similarity 0.82)
• Raising a tone’s level lowers low-frequency pitch but raises high-frequency pitch (similarity 0.81)
• A scale built from pure major-triad intervals yields the just diatonic scale. (similarity 0.81)
• Halving a bar’s length raises transverse modes two octaves but longitudinal modes one octave. (similarity 0.81)