CSound-tutorial.fm

Description

Pierre Couprie6 December 2003UNESCO/DigiArtsMINT/Paris4-Sorbonne Detailed user guide for CSound1. General presentation Name: CSoundCategories: audio processing, editing sequence, analysis, synthesis, mixingPlug-in: NOVersions: 4.23Platforms (systems): Mac (68K, PPC, OS10), Dos, Windows (95, 98, 2000), LinuxURL (last login date):http://www.csounds.com/(6/12/2003)Size of file to download: 1,8 to 2,6 Mo (depending on the version)Language: EnglishSkill level: AdvancedIf you are using this software under Windows, you will need a pure text editor like PurpleEditor: http://www.pcastuces.com/ldj/purpleeditor.htm 2. Technical description - tutorial FormatsImport files: Wave, Aiff ( + other formats that vary depending on the versions)Export files: Wave, Aiff ( + other formats that vary depending on the versions)FunctionalitiesCSound is a successor to the legendary Music V. Like the latter, it requires some patience to learn the various commands. In fact, to produce a sound, you have to start by programming two pure text files in lines of code. There are several manuals and tutorials in English (look on the page http://www.csounds.com/). I have therefore decided, in this short tutorial, to explain a single example that will help to understand one of the functioning principals of the software. CSound is currently extremely developed with many new modules for synthesising through a physical model, granular 1 synthesis or real-time ...

Informations

• Publié par: Endrui
• Nombre de lectures: 40
• Langue: English

Extrait

1

Pierre Couprie

6 December 2003

UNESCO/DigiArts

MINT/Paris4-Sorbonne

Detailed user guide for CSound

1. General presentation

Name: CSound

Categories: audio processing, editing sequence, analysis, synthesis, mixing

Plug-in: NO

Versions: 4.23

Platforms (systems): Mac (68K, PPC, OS10), Dos, Windows (95, 98, 2000), Linux

URL (last login date):

http://www.csounds.com/

(6/12/2003)

Size of file to download: 1,8 to 2,6 Mo (depending on the version)

Language: English

Skill level: Advanced

If you are using this software under Windows, you will need a pure text editor like PurpleEditor:

http://www.pcastuces.com/ldj/purpleeditor.htm

2. Technical description - tutorial

Formats

Import files: Wave, Aiff ( + other formats that vary depending on the versions)

Export files: Wave, Aiff ( + other formats that vary depending on the versions)

Functionalities

CSound is a successor to the legendary Music V. Like the latter, it requires some patience to

learn the various commands. In fact, to produce a sound, you have to start by programming two

pure text files in lines of code.

There are several manuals and tutorials in English (look on the page http://www.csounds.com/

). I have therefore decided, in this short tutorial, to explain a single example that will help to

understand one of the functioning principals of the software. CSound is currently extremely

developed with many new modules for synthesising through a physical model, granular

2

synthesis or real-time processing. I shall not go into the detail of these modules, but rather

advise you to go directly to the various manuals and tutorials.

Two types of files: .orc and .sco

Programming is done in two text files called “orchestra” and “score” (extension: .orc and .sco).

The “orchestra” file contains the definition of the different types of sound. Each type is called

an “instrument”. This file also contains a certain number of settings such as sample rate or the

number of channels.

The “score” file holds the score indicating at which moment which type of sound (which

instrument) is to play as well as some settings for the instruments in the “orchestra” file.

How to edit the code in these files:

- under Macintosh OSX, DOS and Windows in console mode, you can edit directly in the

software

- under Windows 98: use a pure text editor (not NotePad!) such as PurpleEditor

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The various windows under each environments

Using the software under Macintosh OSX

The window shows four tabs (orc, sco, i/o and options) that allow you to access the different

functionalities of the software (the example below contains the file of an extremely complex

sound).

The “orc” tab shows an .orc (orchestra) file and/or lets you edit it.

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The “sco” tab does the same with a .sco (score) file.

If you open an .orc, and if the .sco file with the same name is in the same folder, CSound will

open it automatically.

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The “i/o” tab is a console that shows you the various operations that have been carried out.

Below: state after the synthesis of a sound.

The “options” tab lets you do a number of settings. It is advisable to leave them on their default

values, except the ones for the export format (“File Format”).

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Using the software under Windows 98

The interface under Windows is less intuitive than under OSX.

The first two fields let you situate the two files .orc and .sco (click on “O” and “S”). “Output

File” lets you choose where you put the synthesised sound file and “Output Device” has to do

with the export format. The other controls enable you to set various export format options or

define the various settings for the sound compilation.

When you click on “>” next to one of the first two fields, the software will ask you with which

application to open the file. Choose a software that reads pure text (see PurpleEditor proposed

when downloading). The file will be opened in the chosen software:

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3. Studying an example

We shall now look at a very simple example of programming: the play of an oscillator over 2

seconds at a frequency of 440Hz.

Here is the “orchestra” file:

Comments are indicated in red and always start with a semi-colon symbol.

They are not taken into account during the sound compilation.

sr

= (optional element) sample rate (default rate is 44100)

kr

= (optional element) number of control values per second (4410 by default). The control

values allow you for instance to modify oscillator parameters.

ksmps

= (optional element) number of samples per control period (10 by default). The value

must be equal to sr/kr.

nchnls

= (optional element) number of channels (1 = mono, 2 = stereo, up to 8, or 1 by default)

instr 1

= what follows defines instrument n°1. In CSound, each sound is called an instrument.

kamp

= sound amplitude

kcps

= sound frequency

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These two variables are taken into the oscillator definition (

a1 oscil kamp, kcps

)

out a1

= the oscillator’s sound comes out in 1

And here is the “score” file:

f 1 0 16384 10 1

= defines the wave table used (this is a sinusoid)

i1 0 2

= lets instrument 1 start at 0 seconds and stop after 2 seconds

e

= end of score

4. Comments, tips

Other examples are available on:

http://csounds.com/catalogfrom/

(a certain number is also available on the cdrom, in the “examples” file).