  
Feb 6
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Listen
to and discuss composition I
homework |
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The
Frequency Domain
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Mathematical definition |
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Examples of simple spectra |
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Fourier Transform vs Short-Term
Fourier Transform |
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DFT - Discrete Fourier Transform |
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FFT - Fast Fourier Transform |
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Windowed Short-Term Fourier Transforms |
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Listening
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FM examples, Horner, Beauchamp,
& Haken |
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Tracks 36-38, Current Directions CD |
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Le Souffle du Doux, Daniel Arfib 10:22 |
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Feb 8
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Frequency
Modulation
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Vibrato |
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FM Synthesis |
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Amplitude
Modulation
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Amplitude vibrato |
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Control signal with constant offset |
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Ring modulation of natural sounds |
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Sampling
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Why sampling synthesis? |
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How it works. |
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Advantage: natural sound that is easily
captured |
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Disadvantages: space, controllability |
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Techniques in Nyquist:
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Playing a sound from a file |
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Sampling unit generator |
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Sounds as variables |
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Listening
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Homework 4 |
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Make
an interesting FM instrument behavior in Nyquist. Illustrate the
default behavior and then use stretch, loud, and transpose
transformations. |
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Details:
This is
not a composition (wait until next week). Your task is to create an
interesting sound using FM synthesis. Making a good sound with FM is a
challenge, so the idea is that by the time you find something you like,
you will have explored the FM parameter space and gained some valuable
insights into FM, spectra, etc. |
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This
project should be done entirely
in Nyquist. If we load and run your source code, we should hear an
exact copy of the sound file that you turn in. |
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The
sound file should play a sequence
of 4 sounds:
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The default behavior, e.g.
my-fm-sound() |
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A stretched behavior, e.g. my-fm-sound() ~ 3 |
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A louder or softer behavior, e.g.
loud(-12, my-fm-sound()) |
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A transposed behavior, e.g.
transpose(5, my-fm-sound()) |
You should choose transformation parameters that illustrates your
design clearly. E.g. if your sound gets brighter when it gets louder,
make the loud version loud enough that the change is easy to hear. |
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Grading:
In
grading the homework assignments, we will be looking for evidence that
you did
some careful design and that you understand and use the concept of
behavioral abstraction. You can implement FM in one or two lines, but
it is unlikely that you can make something that sounds interesting
without some careful choices of parameters and careful envelope design.
This what we want to see. Your code should be designed with
transformations in mind. If your instrument has a clear, sharp attack,
but the attack turns into a long, slow onset when the sound is
stretched, this is evidence that you have relied upon default behaviors
rather than customizing the behavior to achieve a characteristic sound
(and points will be deducted). Similarly, if transposition causes
vibrato to speed up, expect to lose points. Your code should be
documented so we understand what behavior you are after. Even if you do
something odd on purpose, we might deduct points unless you indicate
through documented code that you know what you are doing.
Missing
sound file = 80 points
Missing SAL file = 20 points
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Submitting
your homework:
You need to submit two things:
-Your lisp code, named project04.sal
-Your resulting wav file, named project04.wav
Submit these to your proj-04 folder on AFS.
Do not make a .zip file, just submit the two files as-is.
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