Classes | UGens > Buffer | UGens > Generators > Granular

GrainBuf : MultiOutUGen : UGen : AbstractFunction : Object

Granular synthesis with sound stored in a buffer

Class Methods

GrainBuf.ar(numChannels: 1, trigger: 0, dur: 1, sndbuf, rate: 1, pos: 0, interp: 2, pan: 0, envbufnum: -1, maxGrains: 512, mul: 1, add: 0)

Arguments:

numChannels

the number of channels to output. If 1, mono is returned and pan is ignored.

trigger

a kr or ar trigger to start a new grain. If ar, grains after the start of the synth are sample accurate.

dur

size of the grain (in seconds).

sndbuf

the buffer holding a mono audio signal. If using multi-channel files, use Buffer.readChannel.

rate

the playback rate of the sampled sound

pos

the playback position for the grain to start with (0 is beginning, 1 is end of file)

interp

the interpolation method used for pitchshifting grains:

  • 1 = no interpolation
  • 2 = linear
  • 4 = cubic interpolation (more computationally intensive)
pan

determines where to pan the output.

  • If numChannels = 1, no panning is done.
  • If numChannels = 2, panning is similar to Pan2.
  • If numChannels > 2, panning is the same as PanAz.
envbufnum

the buffer number containing a signal to use for the grain envelope. -1 uses a built-in Hann envelope.

maxGrains

the maximum number of overlapping grains that can be used at a given time. This value is set at the UGens init time and can't be modified. Defaults to 512. This can be set lower for more efficient use of memory.

WARNING: The above parameter is new (post SC 3.3.1) and has the potential to break code written <= 3.3.1. This parameter is BEFORE the mul slot, and you may need to update code to account for this difference.
mul
add

Discussion:

All args except numChannels and trigger are polled at grain creation time.

Inherited class methods

Instance Methods

Inherited instance methods

Examples

s.boot;

(
var winenv;

b = Buffer.read(s, Platform.resourceDir +/+ "sounds/a11wlk01-44_1.aiff");
// a custom envelope
winenv = Env([0, 1, 0], [0.5, 0.5], [8, -8]);
z = Buffer.sendCollection(s, winenv.discretize, 1);

SynthDef(\buf_grain_test, { |out, gate = 1, amp = 1, sndbuf, envbuf|
    var pan, env, freqdev;
    // use mouse x to control panning
    pan = MouseX.kr(-1, 1);
    env = EnvGen.kr(
        Env([0, 1, 0], [1, 1], \sin, 1),
        gate,
        levelScale: amp,
        doneAction: Done.freeSelf);
    Out.ar(out,
        GrainBuf.ar(2, Impulse.kr(10), 0.1, sndbuf, LFNoise1.kr.range(0.5, 2),
            LFNoise2.kr(0.1).range(0, 1), 2, pan, envbuf) * env)
}).add;
)

// use built-in env
x = Synth(\buf_grain_test, [\sndbuf, b, \envbuf, -1])

// switch to the custom env
x.set(\envbuf, z)
x.set(\envbuf, -1);

x.set(\gate, 0);