SuperCollider CLASSES


Buffer reading oscillator.


Read the content of a buffer at an index.

In comparison to PlayBuf : PlayBuf plays through the buffer by itself, BufRd only moves its read point by the phase input and therefore has no pitch input. BufRd has variable interpolation.

Class Methods

*ar (numChannels, bufnum: 0, phase: 0, loop: 1, interpolation: 2)

*kr (numChannels, bufnum: 0, phase: 0, loop: 1, interpolation: 2)



Number of channels that the buffer will be. This must be a fixed integer. The architecture of the SynthDef cannot change after it is compiled.

NOTE: If you supply a bufnum of a buffer that has a different numChannels then you have specified to the BufRd, it will post a warning and output the channels it can.

The index of the buffer to use.


Audio rate modulateable index into the buffer.

WARNING: The phase argument only offers precision for addressing 2**24 samples (about 6.3 minutes at 44100Hz).

1 means true, 0 means false. This is modulateable.


1 means no interpolation, 2 is linear, 4 is cubic interpolation.

Inherited class methods

Instance Methods

Inherited instance methods


// read a whole sound into memory
s = Server.local;
// note: not *that* columbia, the first one
b =, Platform.resourceDir +/+ "sounds/a11wlk01.wav");

//use any AUDIO rate ugen as an index generator

{, b, * }.play;
{, b, * }.play;
{, b, * }.play;
{, b, + * }.play;
// original duration
{, b,, ) }.play;

//use a phasor index into the file

{, b,,, 0, }.play;

//change rate and interpolation
x = { arg rate=1, inter=2;, b,, * rate, 0,, 1, inter)

x.set(\rate, 0.9);
x.set(\rate, 0.6);
x.set(\inter, 1);
x.set(\inter, 0);

//write into the buffer with a BufWr
y = { arg rate=1;
    var in;
    in =, 300, 400), 0, 0.1);, b,, * rate, 0,;
    0.0 //quiet

//read it with a BufRd
x = { arg rate=1;, b,, * rate, 0,

x.set(\rate, 5);
y.set(\rate, 2.0.rand);
x.set(\rate, 2);