Minimum-phase reasoning lets frequency responses alone reveal room resonance behavior.

Evidence

Figure 9.11(a) shows a very high resolution (about 3 Hz) steady-state frequency response. Many measuring devices, including some relatively inexpensive laptop-based packages, can generate this kind of data. It has excellent detail in the frequency domain, but it reveals nothing directly about what is happening in the time domain. However, because we know that low-frequency room resonances generally behave in a minimum-phase manner, we know that, if there are no prominent peaks protruding above the average spectrum level, there will not be prominent ringing in the time domain. It is this indirect, inferential, knowledge that permits us to confidently use frequency responses as a primary source of information about room behavior at low frequencies. — Toole, Floyd E, Sound reproduction- the acoustics and…, 952

Categorization

• XREF: The inferential leap from amplitude to time domain is a methodological principle applicable across measurement-driven engineering fields.