Slides 

Mar 3

• Filters
  • Impulse Response
  • Convolution
  • Time domain and spectral domain views
  • Filters in Nyquist
• Delay
• Comb filters
• Reverberation
• Listening
  • Chreode I (1983), Jean-Baptiste Barrier, 9'26"

Mar 5

• 3D Sound
• HRTF
• Room Models
• Doppler Shift
• Multi-speaker playback

Project 8 due Mar 18, 10PM

Make a composition (about 1 minute) Run a voice through a bank of highly resonant filters or through some very resonant comb filters. With enough resonance, these filters will "ring," creating audible pitches that are activated by the input sound. Changing filter frequencies can create melodies or chord changes. Use the amplitude of a voice recording (e.g. see Nyquist functions for peak detection or RMS energy estimation) to control a time varying filter. Changing loudness will then open or close the filter or change the resonant frequency. Randomly change filter frequencies to generate rhythmic (or not) timbral changes.

	Details: All of the comments for Project 5 apply and may help you to plan your work. You do not have to work exclusively with Nyquist. You may use other programs including audio editors (Audacity or other) to manipulate, organize, and mix sounds. You must, however, feature processing of sounds using Nyquist, and you must submit the Nyquist code that you use for this piece. You will use voice sounds that you record as a source that you manipulate and process with Nyquist. You must also submit a short narrative description of your piece: what are you trying to achieve, how did you process sound, and what other software (if any) did you use?
	Grading: In grading the assignments, we will be looking for successful applications of filters to voice to create interesting and musical effects. Most of your effort should be on the effect with the idea that an interesting text will maintain interest for at least a minute. (Therefore you do not have to work out as many compositional details as perhaps in earlier assignments.) In general, a composition that shows evidence of effort will do well. If you make a simple effect and keep everything constant while you run 1 minute of text through it, you will not do as well. Your Nyquist code should be clean and easy to read. Comment your code. If you do not use Nyquist for the final product, you should indicate what the code actually generates and how it was used in the piece.  Please check to make sure that your files are submitted and that they are the right sizes. The deductions for missing parts are listed below. If you are unsure about how to submit your homework, please contact one of the TAs. Missing sound file = 70% Missing lisp file = 20% Missing text description = 10%
	Submitting your homework: You need to submit three things to your proj-08 folder: -Your text description, named project08.txt -Your code, named project08.sal -Your resulting wav file, named project08.wav