Heya folks, I’m not an expert on filter topology, etc. but I’m curious if anyone has been able to get something resembling a pingable LPG with the dual filters/an envelope profile resembling something like vactrol decay. Similiarly, if anyone has any ideas for that richly harmonic complex oscillator sound with the sync/AM I’d love to hear it.
I don’t have my Analog Keys fired up at the moment, but it’s not too difficult to wrangle very “West Coast” sorts of sounds out of a synth like the A4. Especially sounds that depend on the LPG and complex oscillators found in Buchla systems. Here are some things to consider:
The effect of a ‘pinged’ LPG in, say, a “Buchla Bongo” patch isn’t that different from using a simple AR envelope generator to simultaneously close down on amplitude and filter frequency. Vactrol-based circuits like the LPG have a built-in decay time tied to the speed of the Vactrol’s response. Different Vactrols have different times. This is why many LPG circuits have both fast and slow variants (I built a pair of Thomas White’s LPGs into a dual-space panel in my modular, with a slow version on one side and a fast version on the other).
Setting up the envelope(s) will be the trick here, dialing in the desired release time/curve.
Another thing to consider is the timbre of the complex oscillator. Consider using FM to create a more complex waveshape. Would the LFO work here? Cranked up super-high? (like I said, mine isn’t fired up and I’m too lazy to look it up). Even without it, there are some nice sounding analogue waveforms in the Analog Four, so you should be able to find something that works.
If no one else chimes in, I might manage a little time to help you out with this when I am in the studio tomorrow, but I bet you can manage it on your own.
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Great info here thanks! I have a lot to experiment with this weekend.
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Also, consider using a super-short envelope to sweep the pitch of your filter and maybe your oscillator (especially if using FM) if possible.
With a bit of tweaking the Digitone is quite a “Buchla in a tiny box”. Another member here did some really nice videos of this sort of thing. I’ll see if I can find them.
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Very cool, thanks! (As though I need another excuse to get a digitone again)
Also: If you want a cheap solution, you can always look to Korg’s Volca Modular which is very ‘West Coast’ by design.
(but you can likely do something close on the A4 with a bit of fiddling. And Digitone would obviously get you closer, with its FM oscillators)
I actually used to have a Music Easel but found it was too specialized. But while I was running today I realized how similar my A4 is to the Easel, conceptually, and wondered if I could get similar sounds.
Messing around this evening I was able to get a smooth “ping” going here and there and the LFOs do FM at surprisingly high rates on the main oscs.
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Yep, that’s what I thought (though I couldn’t remember for certain). Sounds like you’re well-equipped to tackle the job!
I think modulating pulse width while FMing with the LFO is probably gonna get you pretty close to complex oscillator functions.
Pico System III is another cool little westcoast-ish synth, with mixing linear and exponential FM and an odd waveshaper. Plus it has 2 LPG and 2 Vactrol envelopes.
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