Cgs synth

Great!

Parts changing over time keeps us on our toes, huh? : )

I wish I could use metal cans, just for esthetic reasons. But they're
getting rarer and more expensive.

Scott Deyo
The Bridechamber
contact@...
http://www.bridechamber.com
Jealous Edison Record Kompany
http://www.jealousedison.com

On Sep 15, 2008, at 9:40 PM, Dave wrote:

> Yep, that fixed it :) I'm learning more about this stuff than I
> thought I ever would! Checking data sheets to see whats what. CBE,
> EBC seems simple enough, just gotta know it.
>
> Thanks for the help Scott,
>
> Dave
>
> --- In cgs_synth@yahoogroups.com, Scott Deyo <contact@...> wrote:
> >
> > There you go. The round part of the transistor goes towards the BP
> HP
> > LP holes.
> >
> > Scott Deyo
> > The Bridechamber
> > contact@...
> > http://www.bridechamber.com
> > Jealous Edison Record Kompany
> > http://www.jealousedison.com
> >
> >
> > On Sep 15, 2008, at 7:49 PM, Dave wrote:
> >
> > > I am wondering whether I put the transistors in the right way. I
> am
> > > using TO92 style trans that are black plastic with one flat side.
> > > Right now I have all the 2N2222 and the 2N2907 trans facing the
> same
> > > way with the flat part facing up towards the BP HP and LP holes.
> Is
> > > this correct?
> > >
> > > Thanks,
> > > Dave
> > >
> > > --- In cgs_synth@yahoogroups.com, Scott Deyo <contact@> wrote:
> > > >
> > > > The CV pot is wired the way you say, but terminal 3 is also
> wired to
> > > > ground. (i.e., it's wired as an 'attenuator' or voltage divider
> --
> > > good
> > > > to remember, they're common).
> > > >
> > > > The wiring diagram looks good for freq and res.
> > > >
> > > > Everything has the right orientation -- transistors, diode,
> > > > electrolytics, TL071? The TL071 isn't a TL072? Did you install
> on
> > > the
> > > > links on the board? (I've missed one a few times before.)
> > > > For me, it's usually something painfully obvious once I see it,
> but
> > > for
> > > > some reason I just can't see it though I've looked at it ten
> times.
> > > > Especially on a single-sided board, make sure all your
> soldering is
> > > OK.
> > > > One weak connection can wreak havoc.
> > > >
> > > >
> > > > Scott Deyo
> > > > The Bridechamber
> > > > contact@
> > > > http://www.bridechamber.com
> > > > Jealous Edison Record Kompany
> > > > http://www.jealousedison.com
> > > >
> > > >
> > > > On Sep 15, 2008, at 1:17 AM, Dave wrote:
> > > >
> > > > > Hi Scott,
> > > > >
> > > > > Thanks for the confirmation about the switch wiring :) I'm
> gonna
> > > > > rewire the Decay an Damper pots too. I've tried various switch
> > > > > setting from all off to individual on to all on and they all
> > > react the
> > > > > same to the resonance pot.
> > > > >
> > > > > Is it possible that the wiring diagram is wrong for the res or
> > > freq
> > > > > pots? The freq pot wiring seems a little strange compared to
> the
> > > rest
> > > > > with the 3 leg of the pot wired to the ferrite bead.
> > > > >
> > > > > While I'm at it how do I wire the VCF CV pot? Do I wire from
> EX to
> > > > > the middle lug of the pot and then from terminal 1 on the pot
> to
> > > the
> > > > > jack?
> > > > >
> > > > > Thanks,
> > > > > Dave
> > > > >
> > > > > --- In cgs_synth@yahoogroups.com, Scott Deyo <contact@> wrote:
> > > > > >
> > > > > > I think Decay and Damper are backwards on the CGS diagram.
> > > > > >
> > > > > > It just occured to me that my panel's envelope pot is
> labeled
> > > wrong!
> > > > > > Instead of 0 to 10, it should read -5 to +5. It should be
> at 0
> > > in
> > > > > the
> > > > > > middle, negative envelope to left, positive to right. Ugh!
> > > > > > : (
> > > > > >
> > > > > > It sounds like you have the switches wired up correctly. Try
> > > > > testing it
> > > > > > with just lowpass on at first, and checking the resonance
> again.
> > > > > >
> > > > > > Cheers,
> > > > > > Scott Deyo
> > > > > > The Bridechamber
> > > > > > contact@
> > > > > > http://www.bridechamber.com
> > > > > > Jealous Edison Record Kompany
> > > > > > http://www.jealousedison.com
> > > > > >
> > > > > >
> > > > > > On Sep 14, 2008, at 11:11 PM, Dave wrote:
> > > > > >
> > > > > > > Hi all,
> > > > > > >
> > > > > > > I just finished building a cynare :) But am having
> problems
> > > with
> > > > > > > the filter section. I am building a kit supplied by
> > > bridechamber
> > > > > > > which has three separate SPDT switches for the filter
> types. I
> > > > > have
> > > > > > > added the 6 pots for the osc and also added the impact gen
> > > mod to
> > > > > it
> > > > > > > too (I subbed in a 100k pot for the 25k for now until I
> can
> > > get
> > > > > the
> > > > > > > 25k pot). These mods seem to work correctly. I also
> changed
> > > the R
> > > > > > > gain resistor to 1.5k instead of the 10k.
> > > > > > >
> > > > > > > I followed the CGS wiring diagram exactly assuming that
> the
> > > pot
> > > > > > > shafts are facing away from me and CW is 3 (I am not sure
> > > about
> > > > > this).
> > > > > > > One strange thing I noticed with this is that the Decay
> and
> > > Damper
> > > > > > > pots seem wired backwards so that as I turn it from 0 to
> 10
> > > the
> > > > > decay
> > > > > > > shortens for both, I would think it should lengthen the
> decay
> > > as
> > > > > you
> > > > > > > turn the pot towards 10. The tone or balance between
> noise and
> > > > > > > shimmer operates correctly.
> > > > > > >
> > > > > > > The problem with the filter is that the filter sweep is
> > > minimal
> > > > > > > in effect, the envelope affects the impact sound
> strangely,
> > > when
> > > > > in
> > > > > > > the middle (5) there is little to no impact sound and
> when at
> > > > > either 0
> > > > > > > or 10 the impact is back (sweeping the impact pot mod
> changes
> > > the
> > > > > > > character of the impact sound). The resonance pot is also
> > > acting
> > > > > very
> > > > > > > strange. I have wired the three switches as best I
> > > > > > > knew how which is took the LP, BP, and HP and wired them
> to
> > > the
> > > > > bottom
> > > > > > > lugs of three switches then I wired some bus wire across
> the
> > > three
> > > > > > > middle lugs of the switches and attached the common wire
> to
> > > that.
> > > > > I
> > > > > > > don't know if that is correct but it makes sense to me.
> When I
> > > > > switch
> > > > > > > between the filter types I can hear changes in tone that
> > > > > corresponds
> > > > > > > to the filter type.
> > > > > > >
> > > > > > > Did I wire the three switches correctly, if not how
> should I
> > > do
> > > > > this?
> > > > > > >
> > > > > > > The main malfunction seems to come from the resonance
> pot. It
> > > does
> > > > > > > not increase the resonance and when I turn it all sound
> going
> > > > > through
> > > > > > > the filter is silenced for about 1-2 seconds and then
> comes
> > > back
> > > > > again
> > > > > > > with no change regardless of whether it is at 0 or 10.
> > > > > > >
> > > > > > > I'm new to the DIY so I don't want to mess with things too
> > > much
> > > > > > > while trouble shooting, so I've gone over the board
> looking
> > > for
> > > > > shorts
> > > > > > > and poor connections but have not found anything yet,
> should
> > > I try
> > > > > > > changing some of the wires around on the res pot or maybe
> the
> > > freq
> > > > > > > pot? I'm confused as to why the decay and damper seem to
> > > operate
> > > > > > > backwards from convention and am wondering if I got these
> > > wired
> > > > > > > backwards maybe I wired the res or freq pots backwards but
> > > I've
> > > > > > > checked over and over again and they match up to kens
> > > diagram...
> > > > > > >
> > > > > > > Sorry for the long post :) Any help would be greatly
> > > appreciated,
> > > > > > >
> > > > > > > Thanks,
> > > > > > > Dave
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > >
> > > > > > [Non-text portions of this message have been removed]
> > > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > > [Non-text portions of this message have been removed]
> > > >
> > >
> > >
> > >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>

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