An Indian temple bell’s low tone grows louder over seconds after striking

Evidence

The Indian temple bell exhibits a set of strong frequency components just after the strike (the strike itself is visible as the vertical line at the onset of the sound in both the acoustic pressure time waveform and in the spectrogram, since a brief pulse of energy has a spectrum that is continuous), and finally after about 5 seconds, the output is dominated by a strong low-frequency component whose amplitude grows to a peak and then dies away over a long period of time. Notice that there is a periodic undulation to the output that is visible clearly on the time waveform. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1319

Categorization

• QUESTION: What physical mechanism in the temple bell causes the low-frequency component to grow to a peak after 5 seconds rather than simply decaying? Worth chasing the waveform/coupling explanation.
• CANDY: Nice elevator fact: an Indian temple bell keeps getting louder in its low register for several seconds after the strike before dying away.
• XREF: connects to: An Indian temple bell’s energy shifts between modes over seconds after striking; Indian temple bell energy shifts between modes while singing bowls stay harmonic; The bell reflects low frequencies deep inside and high ones near its rim — David Howard, Jamie Angus, coustics and Psychoacoustics, 1272 (+4 more)

Broader Connections

• An Indian temple bell’s energy shifts between modes over seconds after striking #expands (0.88)
• A struck bell’s overtones enter at different times, shaping perceived timbre. #expands (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1315
• Low-frequency tones become relatively louder as level increases. #corroborates (0.82)
• The bell reflects low frequencies deep inside and high ones near its rim #expands (0.78) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1272
• Indian temple bell energy shifts between modes while singing bowls stay harmonic #qualifies (0.75)
• Low-frequency loudness growth compresses as level rises #complicates (0.74) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1172
• Horn bells boost lower frequencies where wall friction dominates resonance enhancement #qualifies (0.72)