Max package for granular synthesis, originally by Matthias W. Müller - @verenasounds - www.circuitmusiclabs.com. Under maintenance by Cycling '74.
petra is a is a collection of external audio objects neatly packed into a Package for Max by Cycling '74. It is used for polyphonic granulation of pre-recorded sounds. The package is loosely based on the principle of asynchronous granular synthesis (outlined in Curtis Roads' book Microsound). The objects are made for sample precision granulation of both single- and dual-channel audio files.
In addition, petra contains an audio object for live input granulation. It makes use of a circular buffer and an adjustable, and optionally randomised, delay control over the duration of the entire buffer.
All objects share the following controls, which consist of an upper and lower range, from within which a random value is generated for each grain:
- start position within the selected sample buffer~ object
- grain length
- grain pitch
- panorama position per grain
- gain per grain
As of v1.1.0, the petra package will contain a Max for Live Device, which showcases the potential of the external objects:
The device uses the cm.indexcloud~external object and merely serves as an example of what can be done with the objects contained in the petra package. The device can be found in the extras folder.
Drop the Max for Live Device onto a new MIDI Track in Ableton Live and you are ready to go.
Descriptions for all parameters can be viewed in the Ableton Live Info View in the bottom left corner of the Live window. Just hover with the mouse over a parameter and the respective description is displayed.
After installing, open the petra_overview.maxpat file. It contains the entire documentation and links to all object helpfiles.
Please report bugs with the petra package on the GitHub issues tracker.