CGS75 VCS
2010-04-15 by Pete
I was wondering if the VCS would benefit from matching the transistors?
pete
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pete
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Thread
CGS75 VCS
Re: CGS75 VCS
2010-04-15 by Richard Brewster
I hand-matched the two 3904s and the two 3906s. It is simple to do, but
a little hard to describe. I found the technique in Electronotes. How
important this is, I don't know.
Richard Brewster
http://pugix.com
a little hard to describe. I found the technique in Electronotes. How
important this is, I don't know.
Richard Brewster
http://pugix.com
Show quoted textHide quoted text
On 4/15/10 2:36 PM, Pete wrote:
> I was wondering if the VCS would benefit from matching the transistors?
>
> pete
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>
Re: CGS75 VCS
2010-04-15 by Logic Analog
curious myself.
does anyone have a link to the Electronotes technique described by Mr. Brewster???
thanx, MoogFool.
To: cgs_synth@yahoogroups.com
CC: 23isgood@...
From: pugix@...
Date: Thu, 15 Apr 2010 14:48:09 -0400
Subject: Re: [cgs_synth] CGS75 VCS
I hand-matched the two 3904s and the two 3906s. It is simple to do, but
a little hard to describe. I found the technique in Electronotes. How
important this is, I don't know.
Richard Brewster
http://pugix.com
does anyone have a link to the Electronotes technique described by Mr. Brewster???
thanx, MoogFool.
To: cgs_synth@yahoogroups.com
CC: 23isgood@...
From: pugix@...
Date: Thu, 15 Apr 2010 14:48:09 -0400
Subject: Re: [cgs_synth] CGS75 VCS
I hand-matched the two 3904s and the two 3906s. It is simple to do, but
a little hard to describe. I found the technique in Electronotes. How
important this is, I don't know.
Richard Brewster
http://pugix.com
Show quoted textHide quoted text
On 4/15/10 2:36 PM, Pete wrote:
> I was wondering if the VCS would benefit from matching the transistors?
>
> pete
>
>
_________________________________________________________________
[Non-text portions of this message have been removed]
Re: CGS75 VCS
2010-04-15 by Richard Brewster
See page 6 of EN#39. For NPN connect the emitter to ground. Connect a
1.5 Meg resistor between the base and +15V, connect a multimeter
measuring ma (milliamps) between the collector (- lead on the meter) and
+15V. 1ma = HFE of 100, 2.5 ma = HFE of 250, etc. Just select two
transistors with close HFE. For PNP use -15V and reverse the meter
leads. I found that the 2N3904 and 2N3906 had quite different HFE. So
I could not match the NPNs with the PNPs at all. Just the pairs of each
kind.
Richard
1.5 Meg resistor between the base and +15V, connect a multimeter
measuring ma (milliamps) between the collector (- lead on the meter) and
+15V. 1ma = HFE of 100, 2.5 ma = HFE of 250, etc. Just select two
transistors with close HFE. For PNP use -15V and reverse the meter
leads. I found that the 2N3904 and 2N3906 had quite different HFE. So
I could not match the NPNs with the PNPs at all. Just the pairs of each
kind.
Richard
Show quoted textHide quoted text
On 4/15/10 7:02 PM, Logic Analog wrote:
> curious myself.
>
> does anyone have a link to the Electronotes technique described by Mr. Brewster???
>
> thanx, MoogFool.
>
>
>
> To: cgs_synth@yahoogroups.com
> CC: 23isgood@...
> From: pugix@...
> Date: Thu, 15 Apr 2010 14:48:09 -0400
> Subject: Re: [cgs_synth] CGS75 VCS
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> I hand-matched the two 3904s and the two 3906s. It is simple to do, but
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> a little hard to describe. I found the technique in Electronotes. How
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> important this is, I don't know.
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> Richard Brewster
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> http://pugix.com
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> On 4/15/10 2:36 PM, Pete wrote:
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> The CGS Modular Synth home page: http://www.cgs.synth.net/
> Yahoo! Groups Links
>
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>
Re: CGS75 VCS
2010-04-15 by Dave Leith
Here's one article on matching transistors (original moog circuit)
http://www.fantasyjackpalance.com/fjp/sound/synth/synthdata/16-minimoog/002/905-matching-transistor.gif
Here's more info on matching
<http://www.musicfromouterspace.com/analogsynth/TRANSISTORMATCHER/TRANSISTORMATCHER.php>
dave
http://www.fantasyjackpalance.com/fjp/sound/synth/synthdata/16-minimoog/002/905-matching-transistor.gif
Here's more info on matching
<http://www.musicfromouterspace.com/analogsynth/TRANSISTORMATCHER/TRANSISTORMATCHER.php>
dave
Show quoted textHide quoted text
On 4/15/10, Logic Analog <dschnidsky@...> wrote:
>
> curious myself.
>
> does anyone have a link to the Electronotes technique described by Mr. Brewster???
>
> thanx, MoogFool.
>
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>
> To: cgs_synth@yahoogroups.com
> CC: 23isgood@...
> From: pugix@...
> Date: Thu, 15 Apr 2010 14:48:09 -0400
> Subject: Re: [cgs_synth] CGS75 VCS
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> I hand-matched the two 3904s and the two 3906s. It is simple to do, but
>
> a little hard to describe. I found the technique in Electronotes. How
>
> important this is, I don't know.
>
>
>
> Richard Brewster
>
> http://pugix.com
>
>
>
> On 4/15/10 2:36 PM, Pete wrote:
>
> > I was wondering if the VCS would benefit from matching the transistors?
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> > pete
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> _________________________________________________________________
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> [Non-text portions of this message have been removed]
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> ------------------------------------
>
> The CGS Modular Synth home page: http://www.cgs.synth.net/
> Yahoo! Groups Links
>
>
>
>
Re: CGS75 VCS
2010-04-15 by sasami@hotkey.net.au
>I could not match the NPNs with the PNPs at all. Just the pairs of eachThat is not so inportant, as only one pair is used at a time - either the
>kind.
npns or the pnps. It's two differential pairs.
Ken
_______________________________________________________________________
Ken Stone sasami@... otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
Re: CGS75 VCS
2010-04-15 by Pete
Thanks folks for the info.
pete
pete
On Thu, Apr 15, 2010 at 5:02 PM, <sasami@...> wrote:
>
>
> >I could not match the NPNs with the PNPs at all. Just the pairs of each
> >kind.
>
> That is not so inportant, as only one pair is used at a time - either the
> npns or the pnps. It's two differential pairs.
>
> Ken
> __________________________________________________________
> Ken Stone sasami@... <sasami%40hotkey.net.au>
> otherunicorn@...<otherunicorn%40virginbroadband.com.au>
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/<http://www.blaze.net.au/%7Esasami/>
> >
>
>
>
--
www.p23.biz
[Non-text portions of this message have been removed]
Re: CGS75 VCS
2010-04-16 by Logic Analog
thanx Dave!!
see you at the Meet-up.
d.
To: cgs_synth@yahoogroups.com
From: dave.leith@...
Date: Thu, 15 Apr 2010 16:37:37 -0700
Subject: Re: [cgs_synth] CGS75 VCS
Here's one article on matching transistors (original moog circuit)
http://www.fantasyjackpalance.com/fjp/sound/synth/synthdata/16-minimoog/002/905-matching-transistor.gif
Here's more info on matching
<http://www.musicfromouterspace.com/analogsynth/TRANSISTORMATCHER/TRANSISTORMATCHER.php>
dave
see you at the Meet-up.
d.
To: cgs_synth@yahoogroups.com
From: dave.leith@...
Date: Thu, 15 Apr 2010 16:37:37 -0700
Subject: Re: [cgs_synth] CGS75 VCS
Here's one article on matching transistors (original moog circuit)
http://www.fantasyjackpalance.com/fjp/sound/synth/synthdata/16-minimoog/002/905-matching-transistor.gif
Here's more info on matching
<http://www.musicfromouterspace.com/analogsynth/TRANSISTORMATCHER/TRANSISTORMATCHER.php>
dave
Show quoted textHide quoted text
On 4/15/10, Logic Analog <dschnidsky@...> wrote:
>
> curious myself.
>
> does anyone have a link to the Electronotes technique described by Mr. Brewster???
>
> thanx, MoogFool.
>
>
>
> To: cgs_synth@yahoogroups.com
> CC: 23isgood@...
> From: pugix@...
> Date: Thu, 15 Apr 2010 14:48:09 -0400
> Subject: Re: [cgs_synth] CGS75 VCS
>
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> I hand-matched the two 3904s and the two 3906s. It is simple to do, but
>
> a little hard to describe. I found the technique in Electronotes. How
>
> important this is, I don't know.
>
>
>
> Richard Brewster
>
> http://pugix.com
>
>
>
> On 4/15/10 2:36 PM, Pete wrote:
>
> > I was wondering if the VCS would benefit from matching the transistors?
>
> >
>
> > pete
>
> >
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> >
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> __________________________________________________________
>
>
>
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> [Non-text portions of this message have been removed]
>
>
>
>
> ------------------------------------
>
> The CGS Modular Synth home page: http://www.cgs.synth.net/
> Yahoo! Groups Links
>
>
>
>
_________________________________________________________________
Say Happy New Year with Messenger for Mobile.
http://go.microsoft.com/?linkid=9706117
[Non-text portions of this message have been removed]
Re: CGS75 VCS
2010-04-16 by tim.wade@l-3com.com
Juergen Haible "reinvented" the core of the VCS a few years ago and has
a bit of a description of how it works here:
http://www.jhaible.de/tonline_stuff/hj_vc_hadsr.html It is implemented
as a much more conventional ADSR but as he points out the transistors
don't need to be matched...
From: cgs_synth@yahoogroups.com [mailto:cgs_synth@yahoogroups.com] On
Behalf Of Pete
Sent: Friday, 16 April 2010 2:36 AM
To: cgs_synth
Subject: [cgs_synth] CGS75 VCS
I was wondering if the VCS would benefit from matching the transistors?
pete
--
_,___
[Non-text portions of this message have been removed]
a bit of a description of how it works here:
http://www.jhaible.de/tonline_stuff/hj_vc_hadsr.html It is implemented
as a much more conventional ADSR but as he points out the transistors
don't need to be matched...
From: cgs_synth@yahoogroups.com [mailto:cgs_synth@yahoogroups.com] On
Behalf Of Pete
Sent: Friday, 16 April 2010 2:36 AM
To: cgs_synth
Subject: [cgs_synth] CGS75 VCS
I was wondering if the VCS would benefit from matching the transistors?
pete
--
_,___
[Non-text portions of this message have been removed]