it’s it possible to do squarewave pulse width modulation on DN?
One of the factory patches sounds pretty similar, search for the word PWM in the sound explorer.
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You cant do PWM proper since there is no square wave oscillator, and no LFO to pulse width destination. You can approximate it, but its not the real thing.
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PWM is a feature of many subtractive synths. But the DN is a frequency-modulation synth. Totally different sound creation idea. It takes simple waveforms and processes FM. There is no paramter intended to control the width of a created waveform before or after the FM has been done.
So what can we do to achieve a more dense sound, if the wave created by FM doesn’t have enough thickness?
Continuously applied PWM changes the waveshape and hence the frequency spectrum of the sound. This has the effect that the sound gains more richness.
Here some things to try …
- Modulation of the Harmonics. This also changes the spectrum. Try to modulate SYN2 PAGE 2 parameter HARM
- Modulation of the FM intensity. This changes the waveform of the FM process significantly. Try to modulate on SYN2 PAGE 2 the LEV parameter.
The modulation can be done with an LFO.
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Since Digitone cannot set waveform phase, it cannot be completely reproduced, but this page may be helpful.
https://angstromnoises.com/ableton-tutorial-pwm-in-operator/
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this forum is fantastic. I could never have guessed this Q would lead to so much insight
hey Taro. any guess how that could be made in DN? I should check the overbridge. or oscilloscope in a daw
I referred to the above link.
PWM in fm synth
Square Wave(Phase 25%) 
(FM) Square Wave(Phase 0)
Reproduction in Digitone
B2(Phase 0) B1(Phase Free)
- Algorithm = 1 , 2 and 4
- X-Y Mix - Y = 100%
- AB Harmonics = 19.00 =Square wave
- Env Operator B Level = 30~40
- Phase reset = A+B2
- LFO Dest = SYN LEV B
- LFO Depth = 35~40
However, the phase is not constant and cannot be reproduced completely.
Or
[B2→B1] C(Phase Free)
- Algorithm = 1
- X-Y Mix - X = 100%
- Operator B1 : B2 = 1.00 : 2.00 = Waveform like a square wave
- C Harmonics = 19.00 =Square wave
- Env Operator B Level = 8
- Phase reset = A+B2
- LFO Dest = SYN LEV B
- LFO Depth = 19
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So, I was mucking about with the ratio offsets and it seems that while you can’t set the phase you can knock it off dead center manually using the ratio offsets. You just slowly increase the value and then dial it in back to zero without using the function key. Of course the phase is reset with the next note on, but for drones you can adjust the relative phases with without much control. Apart from this, how do you set something to “free phase?”
OK, I tried my hand at coming up with PWM and this is where I ended up:
- Algorithm = 1
- X-Y Mix - X = 100%
- Operator C:A = 1.00 : 1.00
- C Harmonics = -19.00 (Square wave)
- Env Operator A Level = 63
- Amp Drive = 127 (to create a clipped waveform)
- LFO Dest = SYN LEV A
- LFO Depth = 15
Downsides:
Sounds pretty distorted when played polyphonically and the way the pulse width is modulated shifts the sound up an octave.
Conclusions:
PWM should be a an LFO destination that augments the phase accumulator shape from a ramp
to a pair of ramps with different slopes that meet half way up.
This would create a PWM effect effects for other waveforms as well:
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