Exercise 1: Modal Analysis, Synthesis

Name: _______________________________

Instructions: Answer the questions in consise writing

1. Make at least one “typical” recording of your instrument.

1b. If applicable at least one make “impulsive” recordings of your instrument

2. Use fft.exe and notchfft.exe to create sound files that use 5, 20 and 50 modes of the original sound (if impulsive is applicable, use impulsive).
3. Listen to the new sound files
4. Question: Classify the new sound files subjectively between poor and great and explain subjectively the difference.
5. Use fft.exe and peaksfft.exe to find the first 10 modes. Chose the 4 most persistent over the time evolution.
6. Question: How many of the frequencies you found have harmonic (that is integer) ratios?
7. Use the minimum number of modes that resulted in acceptable similarity to the origina from step 4.
8. Modify ModalBar.cpp in STK to model your measured modes. (All you need to do is to modify on of the presets).
9. Create a wav file using STK
10. Use peaksfft.exe and your ear to verify your STK code. Iterate 8-10 until satisfied (compared to the sound generated in 2.).
11. Question: Describe the difference if any between the STK sound and the modal version of the recording it is based on.

12. Have your sound available. You may be asked to send them by email. Don’t send them without request though!