lfo phase reset

[emmanuel63]

Hello,

I try to reset the phase of an LFO to zero each time a note is played. It has no effect. I think I misunderstand to use of phase().

lfo.phase(0); //reset LFO phase
envelope1.noteOn(); //new note

Emmanuel

[UHF]

This has come up several times before on the forum. Have a look here: https://github.com/ElectroTechnique/.../master/TSynth You need to set the phase_accumulator to zero by adding a sync() function that you call:

In synth_waveform.h:

void sync() {
  syncFlag = 1;
}

In synth_waveform.cpp:

if(syncFlag==1){
  phase_accumulator = 0;
  syncFlag = 0;
}

ph = phase_accumulator + phase_offset; //existing code

[MarkT]

Hello,

I try to reset the phase of an LFO to zero each time a note is played. It has no effect. I think I misunderstand to use of phase().

lfo.phase(0); //reset LFO phase
envelope1.noteOn(); //new note

Emmanuel

The phase() call changes the phase of the waveform relative to the original phase, allowing phase modulation
in steps, for instance. It doesn't change the original phase which is set at the time the object is created.

This is not useful for syncing LFO's as you have discovered, but does allow setting up two oscillators in quadrature
for example.

It sounds like there should be a pull-request for adding the sync() call, it does sound useful (or perhaps an absolute
phase call to set the phase_accumulator directly).

By the way when making several changes that should be synchronized use AudioNoInterrupts()/AudioInterrupts() like this:

  AudioNoInterrupts() ;
  lfo.sync();
  lfo.phase(180);
  ...
  envelope1.noteOn();     //new note
  AudioInterrupts() ;

So that all the setup happens atomically w.r.t. the audio system.