Passive vactrol-based VCA anyone?

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futuresoundsystems
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Passive vactrol-based VCA anyone?

Post by futuresoundsystems » Fri Jan 14, 2011 9:16 am

Hello all,

Is anyone here interested in a passive vactrol-based VCA module?

Very simple In-CV-Out jack layout, several VCAs to one small Eurorack panel (2 to every 4HP).
CV can only be DC (positive going) but this is fine for most envelope-based situations.
Vactrol causes some bleed through but from some preliminary tests, it's really not much once the sloping nature of the vactrol has fully decayed.
This sloping means you can feed triggers into the CV inputs and get decay-type envelopes controlling the amplitude.
Cost = not much, looking at around £50-£60 for a dual VCA layout behind a 4HP panel.

Cheers!
Finlay
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a100user
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Post by a100user » Fri Jan 14, 2011 9:33 am

Interesting Finlay

Do you have some audio that demonstrates it?

Thanks

David

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Post by futuresoundsystems » Fri Jan 14, 2011 12:11 pm

David: I'm going to record some audio in a moment, though having looked around there's another available vactrol at a similar price with a much faster response time. Perhaps I should use two vactrol types for each pair of VCAs so one has a slow response and the other has a fast one?
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Post by hollowman » Wed Sep 12, 2012 1:18 am

Long shot.....
But will this ever see the light of day?
Beautiful broken machine.

hawklord2112 wrote:
then again my first two modules were a vca and PLL, wth do i know?

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Post by futuresoundsystems » Mon Oct 15, 2012 4:42 pm

Quite possibly - I'm toying with the idea of releasing some simple utility modules in the near future. Many identical sections but keeping to a low HP count. More to come soon ;)
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Post by madcap » Sun Apr 21, 2013 11:04 pm

Well damn it. I saw the thread and was stoked. No news?

Gotta be a pretty simple circuit. How bout a kit?

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Post by futuresoundsystems » Mon Apr 22, 2013 6:18 am

It's coming... got a few other toys to bring out first though :guinness:
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Post by charonme » Fri Jul 18, 2014 6:53 am

I just got the same idea and I was sure someone already thought of that, so I googled and found this topic and this:
http://electro-music.com/forum/post-397155.html
spotify, bandcamp
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Post by futuresoundsystems » Sun Jul 20, 2014 4:24 pm

Alas, this IS coming, and next on the bill at that 8_)

-Quad layout taking up 6HP
-Sockets for swapping out different vactrols (comes supplied with a set of four)
-(Possible and the only thing left to really test) jumper to turn each VCA into a 6dB/octave LPG approximation. Again, possibly chainable for steeper slopes across four vactrol sections.

So there are a few things to sort out, but this will be out by the end of the year. :banana:
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Post by Guygz » Mon Apr 13, 2015 10:45 am

coming after two end of the year...

is this out?!

cheers

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Post by futuresoundsystems » Tue Apr 21, 2015 7:53 am

Guygz wrote:coming after two end of the year...

is this out?!

cheers
Panels are currently in production. Watch this space. Honest this time.
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Post by charonme » Mon Jan 11, 2016 5:56 am

is this going to be something like the Laurentide Synthworks VG2 ?

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Post by futuresoundsystems » Fri Feb 05, 2016 11:19 am

charonme wrote:is this going to be something like the Laurentide Synthworks VG2 ?
Tada!
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Post by erstlaub » Thu Oct 19, 2017 5:16 am

I'm such a huge fan of this module, it's a no brainer and sounds ace.

I was just curious, if you're prepared to go into it, what's the difference betwen the lpg and vca jumper on the back? Does it just straight bypass the vactrol, does it change the response somehow or is there some other magic happening back there?

Anyway, buy this module, I use it all the time, really great paired with a BSP and a noise source and oscs for instant drums.

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