A room’s acoustic character is captured by a single impulse response

Evidence

The idea of an impulse response (IR) is quite simple: suppose the sound of a sharp click or impulse at the source location is recorded. The sound reflects multiple times from surfaces and gives rise to many clicks at the microphone—the response. What could you predict from this? You could certainly predict the results of two successive clicks, just by adding the response to the first one (which is known) to the second one, which is just the same as the first with the given time delay. If the two clicks were of different amplitude (loudness), there is no need to remeasure, just weight the impulse response with different amplitudes. High-end audio software such as Logic Pro is capable of capture and use of impulse response data. Impulse responses are available on the Internet for many performance spaces, so you can record yourself in a “dry” space and then apply the IR for the Royal Albert Hall to hear what you would sound like performing there! — Eric J. Heller, Why You Hear What You Hear- An…, 489

Categorization

• DEFINE: Explains impulse response as a core concept in acoustics and audio engineering.
• XREF: Connects to convolution and linear systems theory; also to chapter 11’s power spectra which the author flags.
• SEED: The Royal Albert Hall IR application is a vivid hook for a piece on how convolution reverb lets anyone ‘perform’ in famous halls.