[PD] Particlechamber: a 32-voice asynchronous granular synthesizer

derek holzer derek at x-i.net
Tue Nov 11 23:33:06 CET 2003


Particlechamber by Derek Holzer [Umatic.nl]

Particlechamber is a 32-voice asynchronous granular synthesizer for 
real-time transformation of a soundfile. It is loosely based on the 
famous Travelizer instrument from Reaktor 3, however I think it's much 
better because it is FREE!

This abstraction can be used to time-stretch or -compress a soundfile, 
although there are other tools [such as Frank Barknecht's Synchgrain 
object] which do this "nicer", but it's main strength is in generating 
clouds of sonic particles, time-scrambling a file, or creating abstract 
textures. If one does a bit of reverse engineering, it can also be used 
as a tool for learning about the techniques of granular synthesis. I 
have left a subpatch inside the granreader subpatch where others can add 
their own grain-level events, such as randomized or constant-Q filters 
or windowed envelopes, to see what is possible with this technique. Of 
course, I can only highly recommend Curtis Road's amazing book 
"Microsound" for those interested in learning more.


Download Particlechamber here:
http://www.pure-data.org/Members/derek/Particlechamber.zip

Particlechamber requires a few externals to run. It uses Freeverb~ for 
its reverb section [although you could easily replace it with another 
reverb], and uses Grid as a major GUI element [although you could hack 
your way around it if you can't install Grid by sending numbers directly 
to the table_locator subpatch. Look inside for details...]

It would be best to take Grid from the PD External Repository:
http://pure-data.sourceforge.net

However, Yves Degoyon's Grid external can also be found here:
http://ydegoyon.free.fr/software.html

The freeverb~ external can be downloaded here:
http://www.akustische-kunst.org/puredata/main.html


Operation of Particlechamber:

Open the Load subpatch and click the bangs to load samples. It is better 
to do this before you start playing, because loading soundfiles can 
cause audible glitches in PD's performance. Sorry...

The red buttons mute and unmute the file granulator and the reverb. The 
large vertical sliders are gain for each section. The reverb is 
post-fader from the file granulator, and can be bypassed either by 
muting it or with the wet/dry slider.

The envelope is a linear ramp, so a length of 0 means a pure triangular 
"window" for each grain. [(envelope x 2)+length=average grain length in 
ms]. Stereo_spread randomly pans each grain to a wider or lesser field. 
The range feature randomizes each parameter as a percentage plus or 
minus the given number.

Asynch randomizes which grains are passed through, from almost none to 
all. Vox activates or deactivates each of the 32 voices. Grain_spread 
makes small adjustments in the read position, which can be used to 
either add a reverb- or chorus-like effect, or to completely time-smear 
a file. Jitter makes larger adjustments in the read position, resulting 
in various degrees of time-scrambling.

The XY controller at the bottom determines the read position in the 
sample. This controller has an interpolation scale, adjustable by the 
gear-shift on the right. This means that Particlechamber will scan more 
slowly or quickly through the file depending on the cursor's Y position 
multiplied by the interpolation factor.


Particlechamber is free software and comes without any warrenty that it 
will do ANYTHING like what I say it will. Enjoy it all the same.


----------------------------------------------------derek at umatic.nl





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