[actsasbuffoon]

No, the other commenter is correct.

There’s a gate signal, typically activated by holding a key (though in a modular synth, there are many other potential gate sources). While the gate is open an ADSR envelope progresses from Attack -> Decay -> Sustain. It then remains on Sustain until the gate closes, at which point it enters the Release phase. So the amount of time it remains in Sustain is dictated by the gate signal. Notice there’s no G in ADSR, because the gate doesn’t come from the envelope.

What you’re describing is Hold, which some envelopes (AHDSR is one popular flavor) can do. Many Elektron groove boxes have hold stages on their envelopes.

In AHDSR, an open gate goes from Attack into Hold, where it retains its value for a set period of time after the attack, and then goes into the Decay phase and continues from there.

There are plenty of other kinds of envelope, and things that live somewhere between LFOs and envelopes called a function generator, which is often an AR envelope that can be looped. Then there are complex many-stage envelopes that were especially popular when digital synths were first coming onto the scene.

I’d also add that the description you gave of a synth architecture is generally considered East Coast synthesis. One or more oscillators going into a mixer/VCA, and then into a filter and possibly some effects is a very popular architecture made famous by Bob Moog. But there are other forms like West Coast synthesis where instead of having filters, you run gentler wave forms like a triangle through a wave folder, and/or a complex oscillator where you have a pair of oscillators that can cross modulate one another. So where East Coast synthesis takes harmonically rich waveforms and cuts harmonics away with filters, West Coast synthesis starts with harmonically tame waveforms and adds harmonics through various flavors of FM, wave shaping, etc.

Then you’ve got samplers, granular synthesis, physical modeling, additive synthesis, and a bunch of other types as well. The East Coast architecture is popular, but there’s a lot more out there.

[reactordev]

I stand by my comment. It’s time, and no one can convince me otherwise. However, you’re right about East vs West, various LFO combinations, etc but in the end it’s all still very much the same process. You can replace Sampler with Signal, you can replace ADSR with AHDSR or whatever LFO combo you wish but the flow is still the same. Input signal, LFO, output signal for the oscillator, you can take that signal and feed it into another to do FM, you can take that signal and feed it through more LFO’s for that dreamscape, you can take it and send it to master to send out to speakers. The key point here is that no matter what “configuration” your synth is, these things are all the same. Attack is attack. Delay is delay. Etc. once you know what they are, what they do, tweaking them to get the sound you want is mostly trivial (bitcrushing aside)

[actsasbuffoon]

I agree with the overall sentiment. It’s all just a bunch of functions with well defined inputs and outputs that can be combined in a delightfully endless number of configurations. None of it is nearly as complicated as it seems at first glance, and learning how to do it is a ton of fun.