Spaced microphones sound warmer because incoherent signals spread interaural cues

Evidence

However, these techniques have been characterized to lack a ‘sense of space’ (Streicher and Dooley, 1985). One reason for the weak perception of space is that the microphones are directional and are directed typically towards the instruments. The effect of the room, in turn, arrives evenly from all directions, and thus the directional pattern effectively reduces the level of reverberation in the recording. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1840 (#complicates, via linked claim)

A similar dependence of perceived lateral displacement can be obtained if, instead of level differences, differences in the phase of the signals presented to the earphones are used. If, at frequencies below 1500 Hz, the left earphone delivers sound impulses about Ims later than the right earphone, the image shows a lateral displacement totally to the right (R5). If the left earphone leads by 1 ms, the lateral displacement is completely to the left (L5). Between these extreme positions there is a smooth transition. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1714 (#exemplifies, via linked claim)

In order to generate IPM, the overall magnitude of the carrier IPD was held constant throughout the stimulus, but the ear at which the signal was leading in phase was periodically modulated between right and left. Each IPM was applied instantaneously at a minimum in the modulation cycle in order to minimize the (monaural) salience of the instantaneous phase transition (see Fig. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2955 (#qualifies, via linked claim)

Categorization

• XREF: connects to: Directional coincident microphones suppress room reverberation, killing sense of space — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1840; Head shadowing gives roughly 6 dB interaural amplitude difference near 1.85 kHz; Binaural phase disparities improve tone detection by up to 25 dB. (+3 more)

Broader Connections

• Directional coincident microphones suppress room reverberation, killing sense of space #complicates (0.85) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1840
• Interaural level differences of 1-2 dB produce just-audible lateral displacement #exemplifies (0.80) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1714
• Phase transitions hidden at envelope minima decrease monaural detection of interaural cues #qualifies (0.78) — Dijk, Pim van, Physiology, Psychoacoustics and…, 2955
• Head shadowing gives roughly 6 dB interaural amplitude difference near 1.85 kHz #expands (0.75)
• Interaural envelope timing responses weaken with rising carrier frequency and ear mismatch #complicates (0.75)
• Binaural phase disparities improve tone detection by up to 25 dB. #exemplifies (0.72)