«Frequency modulated pulse» by nathanielvirgo

on 26 Aug'11 14:17 in analoguefmpulse

The standard Pulse UGen doesn't sound very good when its pitch is modulated at audio frequencies. This example shows how to produce a band-limited pulse wave that can be modulated at audio rate, producing a better approximation to the kind of FM effects that an analogue modular synth can produce.

Requires sc3-plugins.

log fork json 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
(
// Pulse doesn't respond well to being frequency modulated - loads of weird low freq noise
{ Pulse.ar(SinOsc.ar(XLine.kr(1,8000,20)).range(1,2000))*0.2 !2}.play
)

(
// LFPulse doesn't sound like an analogue synth due to loads of aliasing
{ LFPulse.ar(SinOsc.ar(XLine.kr(1,8000,20)).range(1,2000))-0.5*0.4 !2}.play
)

(
// But you can also produce a good approximation of a pulse wave by clipping a 
// high-amplitude sine wave.  Clipper8 (from sc3-plugins) allows you to do this 
// in a band-limited way.  This sounds much more like a frequency modulated analogue
// oscillator.
{ Clipper8.ar(SinOsc.ar(SinOsc.ar(XLine.kr(1,8000,20)).range(0,2000), 0, 10), -0.2, 0.2) !2}.play
// note: there are two SinOscs - the inner one is the modulator and the outer one is
// clipped to make the pulse wave
)

(
// with PWM too
{ Clipper8.ar(SinOsc.ar(SinOsc.ar(XLine.kr(1,8000,20)).range(50,1000), 0, 10)+LFTri.ar(8,mul:9.9), -0.2, 0.2) !2}.play
)
raw 964 chars (focus & ctrl+a+c to copy)
reception
informative
comments