Hello Cedric!
If you're not so bothered about not so good a sound, but with very good
control, you may use csound or CLM or maybe SuperCollider or PureData. All of
them are programmable synths. I think all of them have GUIs (graphical user
interfaces). You may have a look at
http://www.csounds.com
They have a collection of ready made instruments. Siome of them sound very
good. The plus is always, that you can control them veyr minutely.
I hope this helps.
Warmly yours
Julien
--------
Music was my first love and it will be my last (John Miles)
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