let’s rave about Pulse Width Modulation … possible on the MnM if i remember correctly … also performed by the korg Prophecy … what is this technology, and how do we make it work for new custom sounds?
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Not sure what level you’re at. But there’s a section in this video dedicated to the basics of pulsewidth as a concept.
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very cool. the clavia nord lead 2 manual introduced me to the world of pulse width modulation in 1998 … in fact, the nord lead 2 manual is on the same level as the machinedrum manual, or the monomachine manual == very cool.
cheers for the link. shall watch the video 
and hopefully remember what pwm is all about.
is it like a custom wave made of mini-square waves, thus suited to modelling?
okay i will watch the informative movie 
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Can you PWM waves other than square? I know you can essentially “silence” part of an arbitrary wave and it will create cool timbres. Would that be considered PWM if you were playing only the first or last 20% of a waveform? What would you call it if you kept the same pitch but squeezed the entire wave cycle down into 20% of the period?
NICK BLATT YOU ARE BEING CALLED!!
I really love the options on the A4. It just keeps giving.
There’s an exploration of doing it with sine waves on the Monomachine here: Tips on sine-width modulation
hahah
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You can also do a bit of “approximate” pulse-width modulation by detuning two saw waves a bit. It will be like PWM but the tops of the waves will be a bit slanted like saws. Sounds pretty much the same though. It’s in one of those Sound on Sound synth tips articles I think. So yes, possible on the MNM using the “true” way but also using DoubleDraw with the Saws and a dash of detune.
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Different synths have different wave shaping functions. Analog Keys/Four for example can shape all oscillator waveforms with the PW parameter. Not strictly pulsewidth on all but the square wave. But in answer to your question: Yes, kinda!
From the AK/A4 manual:
OSCILLATORS
Several waveforms are available to the two oscillators of each synth track. By adjusting the PW parameter, the waveshape can be changed on all types of waveforms, changing their timbre. Furthermore, each oscillator has a dedicated PWM LFO, giving animation to the sound by means of pulsewidth modulation.
SAW. This waveform has a biting, buzzy and distinct sound. It contains all harmonics, both odd and even, of the fundamental frequency. Classic synth basses, strings and brass sounds are often created using sawtooth wave- forms. The PW parameter brings in a second sawtooth, out of phase with the first one. Changing the PW value or engaging PWM varies the phase difference between the two, similar to having two slightly detuned oscillators running. This is useful to get a thicker sawtooth sound with more movement as different harmonics interfere with each other. To get a regular single sawtooth, set PW to mid position or either extreme value.
TRANSISTOR PULSE Transistor pulse is special sort of pulse waveform, suitable when you want to achieve acid-like sounds. It sounds a bit more shrill compared to the regular pulse waveform available to the oscillators. PW sets the width of the upper and lower parts of the wave, just like on the regular pulse waveform described below. The major difference is that one part of the transistor pulse waveform is not flat, but rather sloping a bit, thus displaying a slightly similar form as a sawtooth waveform. This introduces more even harmonics, making the sound less hollow. Extreme PW settings, positive or negative, will mute the waveform as the upper or lower part disappears completely. A change in pitch also changes the waveform and pulsewidth a bit, giving slightly different sound at different pitches.
PULSE When the PW parameter is set to its middle value of 0, a square wave will be produced. A square wave contains only odd-numbered harmonics of the fundamental frequency and has a hollow sound, not quite as full as a sawtooth waveform. Changing the PW makes the pulse waveform asymmetric, introducing even harmonics and making the sound thinner and more nasal. Using PWM to introduce pulsewidth modulation is the most clas- sic way of adding animation to a synthesizer waveform. When you want to recreate the sounds of old video games, square waves are very handy. Extreme PW settings, positive or negative, will mute the waveform, as the upper or lower part disappears completely.
TRIANGLE A triangle waveform has a mellow and dampened sound, reminiscent of a mix between a pure sine wave and a square wave. A triangle wave contains only odd-numbered harmonics, but at lower levels than a square wave. A low-pass filtered triangle wave will sound very much like a sine wave. The PW parameter intro- duces an edge in the waveform, gradually changing it from a pure triangle at mid position to a reversed sawtooth waveform at extreme PW settings.
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some vaguely relevant information i found while researching…
Pulse Width Modulation, or PWM, is a technique for getting analog results with digital means. Digital control is used to create a square wave, a signal switched between on and off.
A pulse is a burst of current, voltage, or electromagnetic-field energy. In practical electronic and computer systems, a pulse may last from a fraction of a nanosecond up to several seconds or even minutes.
A duty cycle is the percentage of one period in which a signal or system is active.Duty cycle is commonly expressed as a percentage or a ratio. A period is the time it takes for a signal to complete an on-and-off cycle.
Biological systems
The concept of duty cycles is also used to describe the activity of neurons and muscle fibers. In a biological neural network for example, a duty cycle specifically refers to the proportion of a cycle period in which a neuron remains active.
Generation
One way to generate fairly accurate square wave signals with 1/n duty factor, where n is an integer, is to vary the duty cycle until the nth-harmonic is significantly suppressed. For audio-band signals, this can even be done “by ear”; for example, a -40dB reduction in the 3rd harmonic corresponds to setting the duty factor to 1/3 with a precision of 1% and -60 dB reduction corresponds to a precision of 0.1%.
Space vector modulation
Main article: Space vector modulation
Space vector modulation is a PWM control algorithm for multi-phase AC generation, in which the reference signal is sampled regularly; after each sample, non-zero active switching vectors adjacent to the reference vector and one or more of the zero switching vectors are selected for the appropriate fraction of the sampling period in order to synthesize the reference signal as the average of the used vectors.