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Interested in Trapezoid VCA PCB?

Interested in Trapezoid VCA PCB?

2010-07-25 by JH.

I wonder how many interest there would be in a PCB for a Trapezoid VCA.

It would - of course - be designed to emulate the behaviour of the famous EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a direct copy of the EMS circuit.
Usual pricing for my PCBs, no exotic components needed, rather easy to build, no component selection necessary.

Let me know.

JH.

Re: [motm] Interested in Trapezoid VCA PCB?

2010-07-25 by Chris Coady

hey hey JH,
I would be interested in that. sounds like a really cool addition.

thanks!
chris coady
ccoady1@...







________________________________
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From: JH. <jhaible@...>
To: synth diy <synth-diy@...4all.nl>; analogue@...; 
motm@yahoogroups.com
Sent: Sun, July 25, 2010 1:16:59 PM
Subject: [motm] Interested in Trapezoid VCA PCB?

  
I wonder how many interest there would be in a PCB for a  Trapezoid VCA.

It would - of course - be designed to emulate the  behaviour of the famous EMS 
Synthi A and VCS3 Trapezoid, and it would be - of  course - not be a direct copy 
of the EMS circuit. 

 
Usual pricing for my PCBs, no exotic components needed,  rather easy to build, 
no component selection necessary.

Let me know. 

JH.

Re: Interested in Trapezoid VCA PCB?

2010-07-25 by JH.

Forgot to mention this:
The circuit can run on either +/-15V, or +/-12V, or be self-supplied with a small transformer or AC wallwart.
So apart from using it in the usual modular systems, it would also make a nice pedal or tabletop unit.
In addition to the EMS original function, there will be an "Initial Gain" pot for the VCO, so you can run your signal thru the VCA circuit just for coloration, but with permanent gain, and then gradually blend in the modulation.
I guess I have to make some demo mp3's playing my Farfisa organ thru this. :)
JH.
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----- Original Message -----
From: JH.
Sent: Sunday, July 25, 2010 7:16 PM
Subject: Interested in Trapezoid VCA PCB?

I wonder how many interest there would be in a PCB for a Trapezoid VCA.

It would - of course - be designed to emulate the behaviour of the famous EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a direct copy of the EMS circuit.
Usual pricing for my PCBs, no exotic components needed, rather easy to build, no component selection necessary.

Let me know.

JH.

Re: Interested in Trapezoid VCA PCB?

2010-07-25 by JH.

Quick and dirty demo.
Farfisa VIP 500 thru the Trapezoid VCA + Phaser + BBD Delay
JH.
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----- Original Message -----
From: JH.
Sent: Sunday, July 25, 2010 7:16 PM
Subject: Interested in Trapezoid VCA PCB?

I wonder how many interest there would be in a PCB for a Trapezoid VCA.

It would - of course - be designed to emulate the behaviour of the famous EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a direct copy of the EMS circuit.
Usual pricing for my PCBs, no exotic components needed, rather easy to build, no component selection necessary.

Let me know.

JH.

Re: [motm] Interested in Trapezoid VCA PCB?

2010-07-26 by Richard Brewster

I'm confused. Doesn't trapezoid refer to the shape produced by the envelope generator? What is a Trapezoid VCA?

Thanks,

Richard Brewster
http://pugix.com

On 7/25/10 1:16 PM, JH. wrote:
Show quoted textHide quoted text
I wonder how many interest there would be in a PCB for a Trapezoid VCA.

It would - of course - be designed to emulate the behaviour of the famous EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a direct copy of the EMS circuit.
Usual pricing for my PCBs, no exotic components needed, rather easy to build, no component selection necessary.

Let me know.

JH.

Re: [AH] Interested in Trapezoid VCA PCB?

2010-07-26 by cheater cheater

So what functions does it have currently? I'm not that familiar with
the Synthi :)

My memory says it's a looping envelope + vca, but is that so?

Where does the "coloration" that you mention come from in the vca -
does it use some special topology?

Cheers,
D.
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On Sun, Jul 25, 2010 at 19:16, JH. <jhaible@...> wrote:
> I wonder how many interest there would be in a PCB for a Trapezoid VCA.
>
> It would - of course - be designed to emulate the behaviour of the famous
> EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a
> direct copy of the EMS circuit.
>
> Usual pricing for my PCBs, no exotic components needed, rather easy to
> build, no component selection necessary.
> Let me know.
>
> JH.
>

Re: [motm] Interested in Trapezoid VCA PCB?

2010-07-26 by JH.

It's an envelope generator (which can be used to modulate anything, filters etc.) *plus* a (very special) FET-based VCA.
JH.
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----- Original Message -----
To: JH.
Sent: Monday, July 26, 2010 2:32 AM
Subject: Re: [motm] Interested in Trapezoid VCA PCB?

I'm confused. Doesn't trapezoid refer to the shape produced by the envelope generator? What is a Trapezoid VCA?

Thanks,

Richard Brewster
http://pugix.com

On 7/25/10 1:16 PM, JH. wrote:
I wonder how many interest there would be in a PCB for a Trapezoid VCA.

It would - of course - be designed to emulate the behaviour of the famous EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a direct copy of the EMS circuit.
Usual pricing for my PCBs, no exotic components needed, rather easy to build, no component selection necessary.

Let me know.

JH.


Re: [motm] Interested in Trapezoid VCA PCB?

2010-07-26 by Richard Brewster

Ah! In that case, yes, I'd be interested in a PC board!

Richard Brewster
http://pugix.com

On 7/26/10 1:26 AM, JH. wrote:
Show quoted textHide quoted text
It's an envelope generator (which can be used to modulate anything, filters etc.) *plus* a (very special) FET-based VCA.
JH.
----- Original Message -----
To: JH.
Sent: Monday, July 26, 2010 2:32 AM
Subject: Re: [motm] Interested in Trapezoid VCA PCB?

I'm confused. Doesn't trapezoid refer to the shape produced by the envelope generator? What is a Trapezoid VCA?

Thanks,

Richard Brewster
http://pugix.com

On 7/25/10 1:16 PM, JH. wrote:
I wonder how many interest there would be in a PCB for a Trapezoid VCA.

It would - of course - be designed to emulate the behaviour of the famous EMS Synthi A and VCS3 Trapezoid, and it would be - of course - not be a direct copy of the EMS circuit.
Usual pricing for my PCBs, no exotic components needed, rather easy to build, no component selection necessary.

Let me know.

JH.