First Sounds with SuperCollider

Boot a Server

Synthesis and processing happens inside an SC server. So the first thing to do when creating sound with SuperCollider is to boot a server. The ScIDE offers menu entries for doing that. However, using code for doing so increases the flexibility. In this first example we will boot the default server. It is per default associated with the global variable s:

// boot the server
s.boot;

A First Node

In the SC server, sound is generated and processed inside synth nodes. These nodes can later be manipulated, arranged and connected. A simple node can be defined inside a function curly brackets:

// play a sine wave
(
{
    // calculate a sine wave with frequency and amplitude
    var x = SinOsc.ar(1000);

    // send the signal to the output bus '0'
    Out.ar(0, x);

}.play;

)

UGens

Inside the synth node, the UGen (Unit Generator) SinOsc is used. UGens are the binary building blocks for signal processing on the server. Most UGens can be used with audio rate (.ar) or control rate (.kr).

In the ScIDE, there are several ways to get information on the active nodes on the SC server. The node tree can be visualized in the server menu options or printed from sclang, by evaluating:

s.queryAllNodes

After creating just the sine wave node, the server will show the following node state:

NODE TREE Group 0
   1 group
      1001 temp__1

The GUI version of the node tree looks as follows. This representation is updated in real time, when left open:

/images/basics/sc-nodes-1.png

Note

The server itself does not know any variable names but addresses all nodes by their ID. IDs are assigned in an ascending order. The sine wave node can be accessed with the ID 1001.

Removing Nodes

Any node can be removed from a server, provided its unique ID:

s.sendMsg("/n_free",1003)

All active nodes can be removed from the server at once. This can be very handy when experiments get out of hand or a simple sine wave does not quit. It is done by pressing Shift + . or evaluating:

// free all nodes from the server
s.freeAll

Running SC Files

SuperCollider code is written in text files with the extensions .sc or .scd. On Linux and Mac systems, a complete SC file can be executed in the terminal by calling the language with the file as argument:

$ sclang sine-example.sc

The program will then run in the terminal and still launch the included GUI elements.