Where the delay parameter is defined?

mynkit · 11 January 2022 05:53

I know the TidalCycles delay effect is defined below.

musikinformatik/SuperDirt/blob/44ef3ef35d6d0cd94405596ca41241c1331ebf09/synths/core-synths-global.scd#L77-L127

    
      
          	if(\SwitchDelay.asClass.notNil) {
          
          
		SynthDef("dirt_delay" ++ numChannels, { |dryBus, effectBus, gate = 1, delaytime, delayfeedback, delaySend = 1, delayAmp = 1, lock = 0, cps = 1|
          			var signal;
          			var input = In.ar(dryBus, numChannels);
          			var maxDelayTime = 4;
          
          
			input = input * delaySend.lag(LFNoise1.kr(1).range(0.01, 0.02)); // regulate input
          
          
			delayfeedback = delayfeedback.max(0);
          			delaytime = delaytime * if(lock, reciprocal(cps), 1);
          			delaytime = delaytime.clip(0, maxDelayTime); // just to be sure
          			// from sc3-plugins
          			signal = \SwitchDelay.asClass.ar(input, 1, 1, delaytime, delayfeedback, maxDelayTime);
          
          
			DetectSilence.ar(signal, time:1, doneAction: 1);
          			// doesn't work properly. We don't really know when it's not used anymore.
          			// this would have to be an explicit signal from sclang
          
          
			signal = signal * EnvGen.kr(Env.asr, gate, doneAction:2);

This file has been truncated. show original

It contained a delaytime and delayfeedback parameters, but I can't find where the delay parameter is defined.

Could you tell me this.

Thank you.

ndr_brt · 11 January 2022 10:38

delay is translated to delayAmp here:

github.com

musikinformatik/SuperDirt/blob/develop/classes/DirtEvent.sc#L128

    
      
          		if (~timescale.notNil) {sustain = sustain * ~timescale };
          		~sustain = sustain - (~fadeTime + ~fadeInTime);
          		~speed = speed;
          		~endSpeed = endSpeed;
          
          
	}
          
          
	finaliseParameters {
          		~channel !? { ~pan = ~pan.value + (~channel.value / ~numChannels) };
          		~pan = ~pan * 2 - 1; // convert unipolar (0..1) range into bipolar one (-1...1)
          		~delayAmp = ~delay ? 0.0; // for clarity
          		~latency = ~latency + ~lag.value + (~offset.value * ~speed.value.abs);
          	}
          
          
	getMsgFunc { |instrument|
          		var desc = SynthDescLib.global.at(instrument.asSymbol);
          		^if(desc.notNil) { desc.msgFunc } { ~msgFunc }
          	}
          
          
	sendSynth { |instrument, args|
          		var group = ~synthGroup;

mynkit · 11 January 2022 12:05

Awesome!! Thank you!!!

joanq · 6 December 2022 17:33

I'll resurrect this, as my questions are related.

I'm looking into audio effects, to better understand how they work and hopefully at some point improve the now scarce documentation about them.

Regarding delay, I see on the superdirt part there are like two variations of the basic delay effect, the first one is using delaySend and the second one isn't (so I suppose is like a send effect vs an insert effect). But I can't find the two variations on the Tidal part.

Also, I see in supercollider there are several delay effects implemented. For example, pingpong delay would be cool to have on tidal. Are these ported? Can be used from Tidal even if not (like, there are some functions that let you use functions directly from supercollider but inside tidal)? If not, are they easy to port?

I hope I'm making sense, it's a bit confusing when you start to dig into the different code layers.

Finally, this is probably a bug. Notice the difference between d1 $ sound "bd sn" # delay 1 # delaytime (1/4) # lock 1 # pan 0 and d1 $ sound "bd sn" # delay 1 # delaytime (1/4) # lock 1 # pan 0.01. It seems that the delay disappears when pan is set to 0 or to 1.