Air absorption and room acoustics can be modeled as low-pass and arbitrary filters

Evidence

Most commonly, filters are implemented as digital filters using DSP structures, or as analogue filters using electronic circuits. Many acoustic phenomena can be interpreted as filters. For example, the effect of atmospheric absorption of sound is effectively a low-pass filter, and the acoustic effect of a room can also be considered as a filter with an arbitrary response. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 416

A filter modifies the magnitude or phase spectrum of an input signal. Often, filters are applied to attenuate some frequencies and leave others untouched. In most cases, the processing also changes the phase spectrum. In some cases, the filters do not change the magnitude spectrum, but only the phase spectrum. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 413

Categorization

• XREF: This reframes room acoustics and atmospheric absorption as filter responses — connects directly to the reader’s interest in acoustic communication applications and to prior material on room/ambient acoustics. — connects to: Air absorption must be modeled or artificial reverb sounds overbright — David Howard, Jamie Angus, coustics and Psychoacoustics, 1987
• QUESTION: Which specific rooms map to which filter responses — a question to chase in later modeling chapters.
• DEFINE: Defines what a filter does to a signal before the taxonomy of filter types follows.
• corroborated: 2 independent passages support this claim — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 416; Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 413