3 VCA's in comparison

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neandrewthal
full clout y'all
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Post by neandrewthal » Wed Dec 31, 2008 6:14 pm

:deadbanana:
Initiate the sequence, create catastrophe.

JohnLRice

Post by JohnLRice » Wed Dec 31, 2008 8:17 pm

dougcl wrote:Is it tinnier?
I'm not sure, but it certainly doesn't fill me with confidence!

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Jari Jokinen
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Post by Jari Jokinen » Thu Jan 01, 2009 8:14 am

alex82 wrote:
Jari Jokinen wrote: - Cwejman "log" response is exponential response.
- "Semi-logarithmic" response of Cwejman VCA-4MX is not very different from the "log" response of VCA-2P.
What? You say the log response is a exp. response. Thats not very logical :confused:

I don't know realy whats the diffrence of a semi log. curve and a log. curve, can you explain the diffrence?
According to Cwejman "The semi-logarithmic transfer function is much more practical than a true logarithmic because the semi-logarithmic mode "imitates" the natural behaviour of volume controllers."

The response is between "logarithmic" and linear. However, at least in my VCA-4MX it is *much* closer to the the "log" response of the VCA-2P

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Jari Jokinen
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Post by Jari Jokinen » Thu Jan 01, 2009 8:40 am

RussianDance wrote:
JohnLRice wrote:I haven't tried this with these three VCA's but I'm pretty sure you could get the MOTM or Doepfer to sound pretty much like the Cwejm by adjusting the envelope. I'm not so sure you'd be able to make the Cwejm sound as tight as the MOTM or Doepfer though . . . :hmm:
That's exactly what I thought when I heard the samples. The Cwejman attack seems a bit sluggish.
Here are too examples I made with Cwejman ADSR-VC2 (5V mode) and VCA-2P ("log" mode, full gain). I have a grounding problem in my recording system, which makes the results a bit difficult to judge. Anyway I think, that both units behave as one should expect. Attack is fast, VCA response looks normal and sound is clean.

What might explain the differences in the examples by alex82? Perhaps MOTM and Doepfer VCA:s have (more pronounced) built-in choking/gating near zero CV. At least Serge VCA:s are supposed to have this kind of feature. There might also be some CV clipping present in the attack phase giving more "punch".
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paults
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Post by paults » Fri Jan 16, 2009 12:53 am

The MOTM-1190 VCA in EXP mode does have a faily steep curve, so that for control voltages from 0-2.5V not a whole lot is going on (the output amplitude is down maybe 40dB).

You can compensate for this by simply adjusting the INITIAL (gain) panel control. This adds a fixed CV, and so you can set very precisely where the VCA starts to 'turn on' anywhere along the curve. In this manner, you can get all sorts of responses.

Also, the output stage has a "soft clipper" function that sounds really nice, and for large inputs can actually do a bit of waveshaping.

JohnLRice

Post by JohnLRice » Fri Jan 16, 2009 1:07 am

paults wrote:The MOTM-1190 VCA in EXP mode does have a faily steep curve, so that for control voltages from 0-2.5V not a whole lot is going on (the output amplitude is down maybe 40dB).

You can compensate for this by simply adjusting the INITIAL (gain) panel control. This adds a fixed CV, and so you can set very precisely where the VCA starts to 'turn on' anywhere along the curve. In this manner, you can get all sorts of responses.

Also, the output stage has a "soft clipper" function that sounds really nice, and for large inputs can actually do a bit of waveshaping.
. . :party: . . :party: . . :party: . .

:hihi: Welcome Paul!!!!!! :hihi:

. . :party: . . :party: . . :party: . .

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Muff Wiggler
wait, what?
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Post by Muff Wiggler » Fri Jan 16, 2009 3:44 am

welcome Paul :party:

good to have you here


now listen,

Paul and Peake are not allowed in the same thread as each other.

help me out guys :help:








:oops: i'm just kiddin' :razz:

for real good to have you here 8)

Norman_Phay

Post by Norman_Phay » Fri Jan 16, 2009 6:57 am

World War 2 was a hoax, designed and carried out by the global financial "illuminati" purely in order to boot the global economy out of the depression. All those clips of D-Day, Stalingrad etc? Coreographed by Busby Berkeley in his spare time, in between making Alice Faye and Esther Williams musicals.

Norman_Phay

Post by Norman_Phay » Fri Jan 16, 2009 6:58 am

OK, should I delete that, or put in a link to the forum I meant to post it on, eh?

:bang:

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