Cgs synth

On 12/19/12 10:00 PM, adematteo wrote:
> Hi guys,
> I recently built up the vca3 boards and didn't realize until after the fact that it's recommended to match the bc548's.
>
> The fact that it's mentioned on Kens page makes me wonder if i should pull them and match them (ie. how critical is this ?) ?
>
> Which leads to my second question what are we measuring and how are we doing it ?
>
> I planned on building up Ian Frijtz's Transistor matching circuit for the dual transistors on this and the vco boards so would i be able to use this circuit to match the bc548's as well ?
>
> Thanks for any insight you guys can offer,
> -Tony
>
>



[Non-text portions of this message have been removed]

--- In cgs_synth@yahoogroups.com, Richard Brewster <pugix@...> wrote:
>
> Last week I built a DUSG and matched the transistors using the method
> described in Electronotes #39, p. 6. It's much simpler than Ian
> Frijtz's method, which I tried first. I had trouble getting enough
> resolution on my measurement, only two digits of precision. With the EN
> approach, I got three digits.
>
> Richard Brewster
> http://pugix.com
>
> On 12/19/12 10:00 PM, adematteo wrote:
> > Hi guys,
> > I recently built up the vca3 boards and didn't realize until after the fact that it's recommended to match the bc548's.
> >
> > The fact that it's mentioned on Kens page makes me wonder if i should pull them and match them (ie. how critical is this ?) ?
> >
> > Which leads to my second question what are we measuring and how are we doing it ?
> >
> > I planned on building up Ian Frijtz's Transistor matching circuit for the dual transistors on this and the vco boards so would i be able to use this circuit to match the bc548's as well ?
> >
> > Thanks for any insight you guys can offer,
> > -Tony
> >
> >
>
>
>
> [Non-text portions of this message have been removed]
>

>Hi guys,
>I recently built up the vca3 boards and didn't realize until after the fact

>
>The fact that it's mentioned on Kens page makes me wonder if i should pull

>
>Which leads to my second question what are we measuring and how are we

>
>I planned on building up Ian Frijtz's Transistor matching circuit for the

>
>Thanks for any insight you guys can offer,
>-Tony
>
>
>
>------------------------------------
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>Yahoo! Groups Links
>
>
>
>

--- In cgs_synth@yahoogroups.com, sasami@... wrote:
>
> If it is working to your satisfaction, leave it alone. :) If the transistors
> are from the same batch, chances are they match already.
> Ken
>
> >Hi guys,
> >I recently built up the vca3 boards and didn't realize until after the fact
> that it's recommended to match the bc548's.
> >
> >The fact that it's mentioned on Kens page makes me wonder if i should pull
> them and match them (ie. how critical is this ?) ?
> >
> >Which leads to my second question what are we measuring and how are we
> doing it ?
> >
> >I planned on building up Ian Frijtz's Transistor matching circuit for the
> dual transistors on this and the vco boards so would i be able to use this
> circuit to match the bc548's as well ?
> >
> >Thanks for any insight you guys can offer,
> >-Tony
> >
> >
> >
> >------------------------------------
> >
> >The CGS Modular Synth home page: http://www.cgs.synth.net/
> >Yahoo! Groups Links
> >
> >
> >
> >
> _______________________________________________________________________
> Ken Stone sasami@... otherunicorn@...
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>

On Wed, Dec 19, 2012 at 10:50 PM, adematteo <adematteo@...> wrote:

> **
>
>
> Thanks Ken, i haven't actually wired it up yet but just noticed the note
> after reading over your page tonight.I'll wire it up and see how it
> sounds.Thanks,Tony
>
>
> --- In cgs_synth@yahoogroups.com, sasami@... wrote:
> >
> > If it is working to your satisfaction, leave it alone. :) If the
> transistors
> > are from the same batch, chances are they match already.
> > Ken
> >
> > >Hi guys,
> > >I recently built up the vca3 boards and didn't realize until after the
> fact
> > that it's recommended to match the bc548's.
> > >
> > >The fact that it's mentioned on Kens page makes me wonder if i should
> pull
> > them and match them (ie. how critical is this ?) ?
> > >
> > >Which leads to my second question what are we measuring and how are we
> > doing it ?
> > >
> > >I planned on building up Ian Frijtz's Transistor matching circuit for
> the
> > dual transistors on this and the vco boards so would i be able to use
> this
> > circuit to match the bc548's as well ?
> > >
> > >Thanks for any insight you guys can offer,
> > >-Tony
> > >
> > >
> > >
> > >------------------------------------
> > >
> > >The CGS Modular Synth home page: http://www.cgs.synth.net/
> > >Yahoo! Groups Links
> > >
> > >
> > >
> > >
> > __________________________________________________________
> > Ken Stone sasami@... otherunicorn@...
>
> > Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> > Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
> >
>
>
>



--
Take care,
Warmth and Peace,
Rich

http://www.damian.deathlehem.com/ - my modular synth
http://www.soundcloud.com/Richarius - my latest composition snippets
http://www.youtube.com/dolphinicus/ - various module videos of mine / etc.


[Non-text portions of this message have been removed]

>Those in the 4 VCAs that have matched trannies (2 I believe and SSM2210s in
>the other 2. 2 more to build.) ... were matched using the ancient Minimoog
>technique.
>For Ian's matching method I DO have a 5 1/2 digit high end bench meter.
>I'm ok there and will be using that method for the next 2, even though my
>latest shipment of 2N3904s are all from the same batch.
>Once it's wired - go through the CV eliminating procedure and all should be
>fine. :)
>
>
>On Wed, Dec 19, 2012 at 10:50 PM, adematteo <adematteo@...> wrote:
>
>> **
>>
>>
>> Thanks Ken, i haven't actually wired it up yet but just noticed the note
>> after reading over your page tonight.I'll wire it up and see how it
>> sounds.Thanks,Tony
>>
>>
>> --- In cgs_synth@yahoogroups.com, sasami@... wrote:
>> >
>> > If it is working to your satisfaction, leave it alone. :) If the
>> transistors
>> > are from the same batch, chances are they match already.
>> > Ken
>> >
>> > >Hi guys,
>> > >I recently built up the vca3 boards and didn't realize until after the
>> fact
>> > that it's recommended to match the bc548's.
>> > >
>> > >The fact that it's mentioned on Kens page makes me wonder if i should
>> pull
>> > them and match them (ie. how critical is this ?) ?
>> > >
>> > >Which leads to my second question what are we measuring and how are we
>> > doing it ?
>> > >
>> > >I planned on building up Ian Frijtz's Transistor matching circuit for
>> the
>> > dual transistors on this and the vco boards so would i be able to use
>> this
>> > circuit to match the bc548's as well ?
>> > >
>> > >Thanks for any insight you guys can offer,
>> > >-Tony
>> > >
>> > >
>> > >
>> > >------------------------------------
>> > >
>> > >The CGS Modular Synth home page: http://www.cgs.synth.net/
>> > >Yahoo! Groups Links
>> > >
>> > >
>> > >
>> > >
>> > __________________________________________________________
>> > Ken Stone sasami@... otherunicorn@...
>>
>> > Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>> > Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>> >
>>
>>
>>
>
>
>
>--
>Take care,
>Warmth and Peace,
>Rich
>
>http://www.damian.deathlehem.com/ - my modular synth
>http://www.soundcloud.com/Richarius - my latest composition snippets
>http://www.youtube.com/dolphinicus/ - various module videos of mine / etc.
>
>
>[Non-text portions of this message have been removed]
>
>
>
>------------------------------------
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>Yahoo! Groups Links
>
>
>
>

On Thu, Dec 20, 2012 at 5:21 AM, <sasami@...> wrote:

> **
>
>
> Wrong transistors! We are talking about the 3x BC548 that drive the matched
> dual transistor.
>
> >Those in the 4 VCAs that have matched trannies (2 I believe and SSM2210s
> in
> >the other 2. 2 more to build.) ... were matched using the ancient Minimoog
> >technique.
> >For Ian's matching method I DO have a 5 1/2 digit high end bench meter.
> >I'm ok there and will be using that method for the next 2, even though my
> >latest shipment of 2N3904s are all from the same batch.
> >Once it's wired - go through the CV eliminating procedure and all should
> be
> >fine. :)
> >
> >
> >On Wed, Dec 19, 2012 at 10:50 PM, adematteo <adematteo@...> wrote:
> >
> >> **
> >>
> >>
> >> Thanks Ken, i haven't actually wired it up yet but just noticed the note
> >> after reading over your page tonight.I'll wire it up and see how it
> >> sounds.Thanks,Tony
> >>
> >>
> >> --- In cgs_synth@yahoogroups.com, sasami@... wrote:
> >> >
> >> > If it is working to your satisfaction, leave it alone. :) If the
> >> transistors
> >> > are from the same batch, chances are they match already.
> >> > Ken
> >> >
> >> > >Hi guys,
> >> > >I recently built up the vca3 boards and didn't realize until after
> the
> >> fact
> >> > that it's recommended to match the bc548's.
> >> > >
> >> > >The fact that it's mentioned on Kens page makes me wonder if i should
> >> pull
> >> > them and match them (ie. how critical is this ?) ?
> >> > >
> >> > >Which leads to my second question what are we measuring and how are
> we
> >> > doing it ?
> >> > >
> >> > >I planned on building up Ian Frijtz's Transistor matching circuit for
> >> the
> >> > dual transistors on this and the vco boards so would i be able to use
> >> this
> >> > circuit to match the bc548's as well ?
> >> > >
> >> > >Thanks for any insight you guys can offer,
> >> > >-Tony
> >> > >
> >> > >
> >> > >
> >> > >------------------------------------
> >> > >
> >> > >The CGS Modular Synth home page: http://www.cgs.synth.net/
> >> > >Yahoo! Groups Links
> >> > >
> >> > >
> >> > >
> >> > >
> >> > __________________________________________________________
> >> > Ken Stone sasami@... otherunicorn@...
> >>
> >> > Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> >> > Australian Miniature Horses & Ponies <
> http://www.blaze.net.au/~sasami/>
> >> >
> >>
> >>
> >>
> >
> >
> >
> >--
> >Take care,
> >Warmth and Peace,
> >Rich
> >
> >http://www.damian.deathlehem.com/ - my modular synth
> >http://www.soundcloud.com/Richarius - my latest composition snippets
> >http://www.youtube.com/dolphinicus/ - various module videos of mine /
> etc.
> >
> >
> >[Non-text portions of this message have been removed]
> >
> >
> >
> >------------------------------------
> >
> >The CGS Modular Synth home page: http://www.cgs.synth.net/
> >Yahoo! Groups Links
> >
> >
> >
> >
> __________________________________________________________
> Ken Stone sasami@... otherunicorn@...
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>
>
>



--
Take care,
Warmth and Peace,
Rich

http://www.damian.deathlehem.com/ - my modular synth
http://www.soundcloud.com/Richarius - my latest composition snippets
http://www.youtube.com/dolphinicus/ - various module videos of mine / etc.


[Non-text portions of this message have been removed]

> Wha'? Who? Whoa ... did I say that? :o Lol. Sorry about that Ken / etc.
> It were 4 or 5 years ago that I built those 4. Maybe it were the 2N3906's
> that I matched that way then. I'll have to check.
>
>
> On Thu, Dec 20, 2012 at 5:21 AM, <sasami@...> wrote:
>
>> **
>>
>>
>> Wrong transistors! We are talking about the 3x BC548 that drive the
>> matched
>> dual transistor.
>>
>> >Those in the 4 VCAs that have matched trannies (2 I believe and SSM2210s
>> in
>> >the other 2. 2 more to build.) ... were matched using the ancient
>> Minimoog
>> >technique.
>> >For Ian's matching method I DO have a 5 1/2 digit high end bench meter.
>> >I'm ok there and will be using that method for the next 2, even though my
>> >latest shipment of 2N3904s are all from the same batch.
>> >Once it's wired - go through the CV eliminating procedure and all should
>> be
>> >fine. :)
>> >
>> >
>> >On Wed, Dec 19, 2012 at 10:50 PM, adematteo <adematteo@...> wrote:
>> >
>> >> **
>> >>
>> >>
>> >> Thanks Ken, i haven't actually wired it up yet but just noticed the
>> note
>> >> after reading over your page tonight.I'll wire it up and see how it
>> >> sounds.Thanks,Tony
>> >>
>> >>
>> >> --- In cgs_synth@yahoogroups.com, sasami@... wrote:
>> >> >
>> >> > If it is working to your satisfaction, leave it alone. :) If the
>> >> transistors
>> >> > are from the same batch, chances are they match already.
>> >> > Ken
>> >> >
>> >> > >Hi guys,
>> >> > >I recently built up the vca3 boards and didn't realize until after
>> the
>> >> fact
>> >> > that it's recommended to match the bc548's.
>> >> > >
>> >> > >The fact that it's mentioned on Kens page makes me wonder if i
>> should
>> >> pull
>> >> > them and match them (ie. how critical is this ?) ?
>> >> > >
>> >> > >Which leads to my second question what are we measuring and how are
>> we
>> >> > doing it ?
>> >> > >
>> >> > >I planned on building up Ian Frijtz's Transistor matching circuit
>> for
>> >> the
>> >> > dual transistors on this and the vco boards so would i be able to use
>> >> this
>> >> > circuit to match the bc548's as well ?
>> >> > >
>> >> > >Thanks for any insight you guys can offer,
>> >> > >-Tony
>> >> > >
>> >> > >
>> >> > >
>> >> > >------------------------------------
>> >> > >
>> >> > >The CGS Modular Synth home page: http://www.cgs.synth.net/
>> >> > >Yahoo! Groups Links
>> >> > >
>> >> > >
>> >> > >
>> >> > >
>> >> > __________________________________________________________
>> >> > Ken Stone sasami@... otherunicorn@...
>> >>
>> >> > Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>> >> > Australian Miniature Horses & Ponies <
>> http://www.blaze.net.au/~sasami/>
>> >> >
>> >>
>> >>
>> >>
>> >
>> >
>> >
>> >--
>> >Take care,
>> >Warmth and Peace,
>> >Rich
>> >
>> >http://www.damian.deathlehem.com/ - my modular synth
>> >http://www.soundcloud.com/Richarius - my latest composition snippets
>> >http://www.youtube.com/dolphinicus/ - various module videos of mine /
>> etc.
>> >
>> >
>> >[Non-text portions of this message have been removed]
>> >
>> >
>> >
>> >------------------------------------
>> >
>> >The CGS Modular Synth home page: http://www.cgs.synth.net/
>> >Yahoo! Groups Links
>> >
>> >
>> >
>> >
>> __________________________________________________________
>> Ken Stone sasami@... otherunicorn@...
>> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>>
>>
>>
>
>
>
> --
> Take care,
> Warmth and Peace,
> Rich
>
> http://www.damian.deathlehem.com/ - my modular synth
> http://www.soundcloud.com/Richarius - my latest composition snippets
> http://www.youtube.com/dolphinicus/ - various module videos of mine /
> etc.
>

--- In cgs_synth@yahoogroups.com, Richard Brewster <pugix@...> wrote:
>
> Last week I built a DUSG and matched the transistors using the method
> described in Electronotes #39, p. 6. It's much simpler than Ian
> Frijtz's method, which I tried first. I had trouble getting enough
> resolution on my measurement, only two digits of precision. With the EN
> approach, I got three digits.
>
> Richard Brewster
> http://pugix.com
>

--- In cgs_synth@yahoogroups.com, "cg_synth" <sasami@...> wrote:
>
> My "dirty little secret" for matching my transistors is to plug them into the HFE test function of a cheap multimeter.
>
> --- In cgs_synth@yahoogroups.com, Richard Brewster <pugix@> wrote:
> >
> > Last week I built a DUSG and matched the transistors using the method
> > described in Electronotes #39, p. 6. It's much simpler than Ian
> > Frijtz's method, which I tried first. I had trouble getting enough
> > resolution on my measurement, only two digits of precision. With the EN
> > approach, I got three digits.
> >
> > Richard Brewster
> > http://pugix.com
> >
>

--- In cgs_synth@yahoogroups.com, sasami@... wrote:
>
> >That's good to know Ken !
> >Do you recommend using the HFE to match the transistors in your vco instead
> of the lm394 ?
> >I'm not concerned about 1v/o tracking being super accurate.
>
> If you aren't worried about accuracy, sure, that would do the trick.
> Separate transistors will never be as good as a dual, due to the thermal lag
> caused by the separation of the transistor dies in their own little epoxy
> packages.
>
> >Also, how do you "join" the 2 transistors together ?
>
> A wire tie around them, with them flat to flat will do the trick. Some
> people go as far as epoxying them together.
>
>
> 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/>
>

--- In cgs_synth@yahoogroups.com, "adematteo" <adematteo@...> wrote:
>
> Thanks Ken, I just wired up the vca and it sounds good to me.
>
> I didn't match the bc548's so maybe i got lucky.
>
> I did match the dual npn's using the HFE test function.
>
> I don't have any trimmers yet so i'm hearing the thump of dc coming through but other than that the source signal sounded good.
>
> Thanks for all your help !
> -Tony
>
> --- In cgs_synth@yahoogroups.com, sasami@ wrote:
> >
> > >That's good to know Ken !
> > >Do you recommend using the HFE to match the transistors in your vco instead
> > of the lm394 ?
> > >I'm not concerned about 1v/o tracking being super accurate.
> >
> > If you aren't worried about accuracy, sure, that would do the trick.
> > Separate transistors will never be as good as a dual, due to the thermal lag
> > caused by the separation of the transistor dies in their own little epoxy
> > packages.
> >
> > >Also, how do you "join" the 2 transistors together ?
> >
> > A wire tie around them, with them flat to flat will do the trick. Some
> > people go as far as epoxying them together.
> >
> >
> > 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/>
> >
>