Loudness-time functions reveal echoes and reverberation better than level-time ones

Evidence

Echoes cause the power spectrum to develop structure. The features resulting from returning echoes are evident in figure 11.2. The first return echo at time T = 1/f induces broad peaks in the power spectrum, spaced by a frequency interval f. The reason for the broad peaks can be seen from the cosine transform, shown for one particular frequency in the middle column in figure 11.2. In the case of the free edge, for example, the product of the cosine of frequency f and the echo is positive at the return time T and adds to the positive contribution at time zero. Thus the second peak lies at frequency f. The first peak is at zero frequency—the proximity resonance. — Eric J. Heller, Why You Hear What You Hear- An…, 1096 (#expands, via linked claim)

Categorization

• corroborated: 2 independent passages support this claim
• XREF: connects to: Cumulative energy time better captures brief-sound perception than reverberation time; A returning echo creates power-spectrum peaks spaced by its inverse time — Eric J. Heller, Why You Hear What You Hear- An…, 1096; High-frequency-resolution waterfalls falsely suggest uncontrolled ringing

Broader Connections

• Cumulative energy time better captures brief-sound perception than reverberation time #corroborates (0.75)
• A returning echo creates power-spectrum peaks spaced by its inverse time #expands (0.70) — Eric J. Heller, Why You Hear What You Hear- An…, 1096