How to change parameters over time in SynthDef

Questions
#1

Hello everyone,

I’m new to this, please excuse if this has been answered before.

How can the durations of the envelope segments be changed over time? I tried to multiply the values using an LFDNoise1.ar for example, but it does not seem to work. I guess I’m missing a basic point here, but I can’t figure it out.

Any help would be greatly appreciated.

(SynthDef.new(\norg,{
	var snd,env;
	env=Env.new([0,1,0],[1, 1]);
	env=EnvGen.ar(env,\gate.kr(1), doneAction: 2);
	snd=SinOsc.ar(\freq.kr(100),0,0.1);
	snd=snd*env;
	Out.ar([-1,1], snd);
}).add)


(Pbind(\instrument,\norg,
	\freq, Pseq((100..200),inf),
	\dur,  Pseq([1,Rest(2)],inf),
).play;
)
#2

Hello and welcome!

It’s generally not a good idea to use modulation (like LFDNoise1) on envelope durations. Instead, I would suggest using controls for \atk and \rel in the SynthDef, and then use Pwhite or Pexprand to set them randomly in the Pbind.

(SynthDef.new(\norg,{
	var snd,env;
    env=Env.new([0,1,0],[\atk.kr(1), \rel.kr(1)]);
	env=EnvGen.ar(env,\gate.kr(1), doneAction: 2);
	snd=SinOsc.ar(\freq.kr(100),0,0.1);
	snd=snd*env;
	Out.ar([-1,1], snd);
}).add)


(Pbind(\instrument,\norg,
	\freq, Pseq((100..200),inf),
	\dur,  Pseq([1,Rest(2)],inf),
    \atk, Pwhite(0.1, 1),
    \rel, Pwhite(0.1, 1)
).play;
)
#3

Also check out DemandEnvGen if you want a way to do this entirely in one SynthDef

https://doc.sccode.org/Classes/DemandEnvGen.html

#4

Thank you so much PitchTrebler and semiquaver. I will try both suggestions and will find out about how they work.

Thanks!

1 Like
#5

I know this thread is a bit old, but you can also use Pseg, which works like an envelope but from a Pbind

#6

Amazing, thank you so much, I will take a look into this. This seems very handy!