Comb-filtering undulations from room reflections move to bass and become inaudible

Evidence

In principle, amplitude panning methods create a comb-filter effect in the ear canal signal spectra, since the same sound arrives from both loudspeakers at each ear with a small time difference. This effect is clearly audible in an anechoic chamber, where it produces a notch in the spectrum between frequencies of 1 kHz and 2 kHz. Fortunately, this effect is not present when listening in a normal room, since the room reverberation mitigates the colouring effect largely (Pulkki, 2001a). — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1890 (#corroborates, via linked claim)

Categorization

• XREF: connects to: A time delay of a reflection imprints a comb of enhanced and suppressed frequencies; Ground reflection colors all outdoor speech and creates comb-filter pitch; Comb filtering is unavoidable and not inherently unpleasant (+6 more)

Broader Connections

• Room reverberation suppresses the comb-filter colouring of amplitude panning #corroborates (0.82) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1890