Assignment 4: Granulation
What we’re trying to do
- Learn how to use the Granulator application.
- Understand several different strategies for producing sound using
- Use creatively what we’ve learned so far this semester in a short
What to turn in
- Three different examples of granulation, in the form of short
(c. 10-20 seconds) sound files, using Granulator. Give the files names
that include “granulation.”
- A short piece that combines some granulated sounds with sounds produced
in Absynth and the spectral processing tools. Make your piece 1 to
2 minutes long — no longer than 2 minutes, please. It can be for
stereo or quad output. (Go
for a refresher on setting up your DP project for quad.)
Put your piece together in Digital Performer, and
bounce to a stereo or quad 16-bit interleaved sound file.
- Submit your 4 sound files (including the piece mix file) in Canvas,
following the assignment submission instructions.
Granulation with Granulator
is an application, built in Max 6, that performs real-time
of sampled sound. To granulate
a sound is to break it
up into many tiny grains
— each anywhere from a few milliseconds
to about a half second in duration. Each grain is subjected to an amplitude
envelope and can be independently transposed. The grains flow out of the
granulator in one or more streams, one grain after another. The time between
successive grains determines the grain rate
, or grain speed
which has a profound impact on the sound. If the grain rate is regular, you may
hear a pitch with a frequency corresponding to the time between successive
grains. If the grain rate is randomly varied, this pitch disappears.
Why would anyone want to granulate sound? The applications range from
time-scaling audio to making a sustained sound out of a short snippet (e.g., a
choral sustain from a guitar pluck) to creating interesting noisy or pulsed
repetitive textures. Play with it to discover.
Granular synthesis does the same thing, but instead of taking grains
from a sound file, it synthesizes grains, using simple wavetable or FM
synthesis. (We don’t have a plug-in that does this.)
One of the first composers to explore granular synthesis, Barry Truax, likes to
use granulation as an audio microscope, zooming in on sound and exploring its
details in slow motion.
Here are some steps to get started using Granulator.
- If you’re working in MC304, Granulator is already installed,
inside /Applications/jgapps/. Drag its icon to your Dock.
- If you want to install Granulator on another Mac,
software and un-zip it, if necessary.
- Launch the program by double-clicking the Granulator file. (Ignore
the granpresets.xml file.)
- If the Mac complains about running something written by an unidentified
developer, launch the program instead by right-clicking (or
control-clicking) on the program icon, and choosing Open in the
dialog box that appears.
- Press the Audio Driver button, and choose the appropriate
item from the Driver pop-up menu. In 304, this should be
- Press the speaker icon to turn on audio.
- Drag a sound file into the empty waveform rectangle.
- Lower the output volume fader, just in case something loud happens.
- Press Play to start granulating. You might need to choose the
top-left square from the Presets grid.
- Drag in the waveform to select a portion to granulate, and fiddle
with the parameters.
- To record the sound you’re making, first set the output format
to 24-bit (either AIFF or WAV), press the Record button,
choose a name and place to store the output file, and press Save.
Granulator will record what you’re doing until you press the
Stop button that is under the Record button.