Transposition for MIDI Keyboard

Questions
1

Hey there

I have the following SynthDef:

(
SynthDef(\saw, {

	arg freq=440,out=0;

	var snd, fft, key, feedb;

	feedb = LocalIn.ar(2);

	snd = LFSaw.ar(freq+LFDNoise3.ar(3,0.7),mul:1).tanh;

	snd = snd+(feedb*0.5);

	LocalOut.ar(snd);

	snd = FreeVerb.ar(snd,0.4,1);

	fft = FFT(LocalBuf(4096), snd);

	key = KeyTrack.kr(fft);

	Out.ar(out,snd);

}).add
)

And I want to use this with a MIDI Keyboard:

MIDIClient.init;
MIDIIn.connectAll;

(
var notes, on, off;

notes = Array.newClear(128); 

on = MIDIFunc.noteOn({ arg veloc, num, chan, src;
	notes[num] = Synth(\saw, [\freq, num.midicps]);
});

off = MIDIFunc.noteOff({ arg veloc, num, chan, src;
    notes[num].release;
});

)

I would like to transpose this Synth one semitone higher. I tried something like “num=num+1” or “(num+1).midicps” but this isn’t doing what I am looking for and I don’t have any ideas left.

Thanks!

2

num.midicps + offset number?

3

Maybe I am doing something wrong. If I try what you suggest it starts to sound a bit more cluster-like on my device. It’s not what I am looking for in this situation.

4

That’s the right basic idea, but there’s some missing detail in your question:

  • Where did you put the num = num + 1 in the code?

  • What did it do that isn’t what you wanted?

That wouldn’t work because midicps outputs Hz, while the offset number is in semitones.

hjh

6

That’s the right basic idea, but there’s some missing detail in your question:

  • Where did you put the num = num + 1 in the code?
  • What did it do that isn’t what you wanted?

Now it works when I write “[\freq, (num+1).midicps]);”

I have no clue why it is behaving different now, but I don’t think I am doing it in a different way than yesterday. Anyway…

7

“That wouldn’t work because midicps outputs Hz, while the offset number is in semitones.”

Thank you, that is pretty convenient to know.

8

tip: you can use .midiratio to multiply hz values like so:

Synth(\default,[\freq,440]) // a
Synth(\default,[\freq,1.midiratio*440]) // one semitone higher
Synth(\default,[\freq,440 / (1.midiratio) ]) // one semitone lower