Day 22

Tuesday, April 25, 2017

Synthesis of drum sound from solution of wave equation on disk

actual drum recording

I tried, but I just cannot match the spectrum of the real drum:

tom_tuning2_closed_spectrum.png

with the theoretical spectrum of the circular membrane:

circular_membrane_spectrum.png

I have to conclude that the either or both of the facts that (i) a drumhead is not a "membrane" (rather a combination of a membrane and a disk which resists being bent) and (ii) the membrane is interacting with a half-closed column of air, result in a spectrum that is quite different that the theoretical one for a stretched membrane alone. :-(

Chapter 8

2017_04_25/ch8.jpg-000.jpg 2017_04_25/ch8.jpg-001.jpg 2017_04_25/ch8.jpg-002.jpg 2017_04_25/ch8.jpg-004.jpg 2017_04_25/ch8.jpg-005.jpg 2017_04_25/20170425_134823.jpg

Chapter 9

2017_04_25/ch9.3-000.jpg 2017_04_25/ch9.3-001.jpg 2017_04_25/ch9.3-002.jpg 9.3_greens_function_example.png