#210

Thanks @simonvanderveldt and @papernoise - super helpful and all makes sense, only just got round to going through these replies…

#211

Is there a VCA out there that gives you CV control over Linear to Exponential response?

#213

Alternatively you could go for a linear VCA and modulate the envelope from linear to exponential …

The ‘old’ MI Tides (2014) has a shape control, that is doing just that.
Or I think multing the envelope out back into the envelope time CV will change a linear into an exponential envelope. Add a VCA to control the amound of CV that is fed back into the envelope time CV. Not straight forward, but …

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#214

Double andore mk2 (which is a vca/env combo) gives you CV control of log/expo response.

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#215

That’s a nice idea. I’d looked at Tallin (like the xaoc stuff) and have Mac.

If I have an envelope that is linear and patch it to both in and level of a VCA, does that make it exponential? or quartic? or is that a multiply function… Just imaging trying to do this with a regular VCA and crossfader of sorts.

#216

Erica’s Pico Mod can be linear or exponential with a built in EG. It pings well, but can’t trigger the entire envelope without a gate; otherwise I like it. Sadly doesn’t work for my own needs, but it’s a very efficient module for the HP.

#217

I’ve recently been using one channel of the sport modulator as an LPG and the other channel as an envelope. Add a VCO and you have a complete voice - Sounds just great. Such a versatile module.

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#219

Just got the Malekko Quad VCA (the only module from their Quad series in my case). It feels like the great mix of size and functions for me. Selecting and changing settings is very fast and the mute buttons are a great addition. Plus there’s a scan feature which is intriguing.

If you already have the Varigate 4+ it seems like a no-brainer as you can save presets but that’s beyond what I need it for.

#220

Fairly basic question, but is there any noticeable difference between processing CV in a VCA vs a LPG? Also if I’m processing audio from a modulator oscillator with an envelope to then send to the carrier’s oscillator’s fm, how would each affect the modulation? Would the filtering in a lpg affect the modulation vs a vca?

#221

If the LPG is vactrol-based, there may be some slewing of the signal, but that depends on how fast the cv is and how slow the LPG reacts. To your second question, I assume it would because as it got quieter, the modulation oscillator would lose high frequency content. Although that may only apply if your modulation signal has harmonic content above its fundamental (i.e. is not a sine wave). Your best bet is probably to try it out and listen closely to the results, both should be interesting!

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#222

Thanks! I don’t have a vca right now, but I’ll ask some buds to test it out.

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#223

A Vactrol usually has a minimum voltage below which the led has no output, similarly it has a “saturation” voltage above which it doesn’t get much brighter. This, combined with non linearity of the LDR means the response is quite different to a VCA. Similarly the amount of hysteresis/slew they exhibit can vary a lot. For some, a clock pulse will make a decay envelope, on some it just gently softens the edges of a gate, the latter being much more vca like. Often you can select how much filtering effect it has (from none to a lot) so for VCA like behaviour, turning the filtering off may help. If the modulation is slow and smooth filtering may have no effect (also the hysteresis/slew matters less in these cases). In short they can function somewhat like a VCA, but how close to a traditional (linear) VCA they behave depends a lot of the nature of the input and CV as well as the vactrol’s characteristics.

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#224

Thank you for the detailed response. Super helpful!