Original Cry-Baby Schematic

[57chevy]

I've just spent 3 hours chasing google links for a schematic for an early
'70's wah-wah....

Cry-baby, Model 95-910511, Thomas Organ Co., Sepulveda, California

I saw many references to this n/g and decided to seek help here. Any info or
link would be most appreciated.

Thanks....Steve

[Jerry]

What specifically do you need to know? That schematic is basically the same as
any other Crybaby schematic you'll find. The newer ones have a buffer circuit
so they don't kill your tone so much. Are you looking for values or do you just
need to know what goes where?
Jerry

[57chevy]

"Jerry" <apinn...@aol.comkissoff> wrote in message
news:20030304231416...@mb-fj.aol.com...

I'm mainly after cap values. These are hard to impossible to read. I can
draw the schematic myself, but I just can't positively identify all the
caps. I found schematics for the Dunlop "Original" Crybaby very quickly, but
struck out on locating a schematic for this particular one. Side by side
visual comparison indicates posible value changes between the Dunlop model
and the Thomas model. The Thomas is a simple 2 Q version with a SPDT switch.
Also, the pot is extremely scratchy with dropouts, and is not original as
evidenced by the sloppy solder job and the obvious hack sawn shaft. I'm
hoping the Dunlop 100K hot potz is the proper replacement. Any clues???

Thanks for the quick response....Steve

[Kate Ebneter]

57chevy wrote:

> I'm mainly after cap values. These are hard to impossible to read. I can
> draw the schematic myself, but I just can't positively identify all the
> caps. I found schematics for the Dunlop "Original" Crybaby very quickly, but
> struck out on locating a schematic for this particular one. Side by side
> visual comparison indicates posible value changes between the Dunlop model
> and the Thomas model.

Doubtless. The Dunlop is a rather different beast. Try here:

http://fuzzcentral.tripod.com/mckoy.html

The CryBaby and the Vox were the same circuit for a very, very, very
long time. The main thing that changed prior to Dunlop taking over
was the inductor, and its value didn't change, just its manufacturer.
So the schematic on fuzzcentral should match your pedal.

The Thomas is a simple 2 Q version with a SPDT switch.
> Also, the pot is extremely scratchy with dropouts, and is not original as
> evidenced by the sloppy solder job and the obvious hack sawn shaft. I'm
> hoping the Dunlop 100K hot potz is the proper replacement. Any clues???

The Dunlop Hot Potz will work, but you might be happier with one of
Mike Fuller's pots, available direct from Fulltone and about the same
price. It's a damned shame Geoffrey Teese no longer sells his pot
separately, because it's as close to an original as you'll get ... but
Fuller's is really good as well, and much better, IMHO, than the
Dunlop.

Kate Ebneter
Collector of Noise Toys

[Jerry]

The schematic Kate gave is right. The .01uf and the 68K at the input will be
reversed on a Thomas Organ but other than that it's the same.
Jerry

[57chevy]

Thanks Kate! You really came through on this one.

"Kate Ebneter" <ebn...@ix.netcom.com> wrote in message
news:3E659476...@ix.netcom.com...

> 57chevy wrote:
>
> > I'm mainly after cap values. These are hard to impossible to read. I can
> > draw the schematic myself, but I just can't positively identify all the
> > caps. I found schematics for the Dunlop "Original" Crybaby very quickly,
but
> > struck out on locating a schematic for this particular one. Side by side
> > visual comparison indicates posible value changes between the Dunlop
model
> > and the Thomas model.
>
> Doubtless. The Dunlop is a rather different beast. Try here:
>
> http://fuzzcentral.tripod.com/mckoy.html

This schematic was verrrrry close, only 2 minor differences between the Vox
diagram and my actual Thomas pedal.

>
> The CryBaby and the Vox were the same circuit for a very, very, very
> long time. The main thing that changed prior to Dunlop taking over
> was the inductor, and its value didn't change, just its manufacturer.
> So the schematic on fuzzcentral should match your pedal.
>
> The Thomas is a simple 2 Q version with a SPDT switch.
> > Also, the pot is extremely scratchy with dropouts, and is not original
as
> > evidenced by the sloppy solder job and the obvious hack sawn shaft. I'm
> > hoping the Dunlop 100K hot potz is the proper replacement. Any clues???
>
> The Dunlop Hot Potz will work, but you might be happier with one of
> Mike Fuller's pots, available direct from Fulltone and about the same
> price. It's a damned shame Geoffrey Teese no longer sells his pot
> separately, because it's as close to an original as you'll get ... but
> Fuller's is really good as well, and much better, IMHO, than the
> Dunlop.

The fulltone site was excellent also! There was an actual top view drawing,
including correct component values, of my Thomas board. Many, many thanks!

I've redrawn the Thomas schematic to reflect the 2 minor changes as well as
show the SPDT switch. If you want it let me know. It's only 5k. I could
email you or post on this n/g, if small binaries are not frowned upon.

Once again, thanks for being here!

Take care....Steve

[57chevy]

Thanks for the info Jerry. FYI, there is one other small difference. The
100k resistor parallel to the inductor is really a 33k resistor on my Thomas
board.

Take care....Steve

"Jerry" <apinn...@aol.comkissoff> wrote in message

news:20030305095957...@mb-bd.aol.com...

[Jerry]

>Thanks for the info Jerry. FYI, there is one other small difference. The
>100k resistor parallel to the inductor is really a 33k resistor on my Thomas
>board.
>
>Take care....Steve
>

Whoops....your right......forgot about that one.
Jerry

[Kate Ebneter]

57chevy wrote:
> Thanks for the info Jerry. FYI, there is one other small difference. The
> 100k resistor parallel to the inductor is really a 33k resistor on my Thomas
> board.

Yeah, that's actually the difference between the early "picture" Clyde
McCoy (and the equivalent Cry Baby) and the later "signature" ones. I
have both, and don't notice any huge difference between the two.

BTW, the "signature" Vox I have is actually a so-called "no-name" one,
with a totally blank bottom cover. It has the "signature" Clyde circuit
with the halo inductor and the 33k resistor. It's practically mint; the
best part is that I paid $125 for it at a local store, because the
owner of the store refused to believe his employee, who'd been educated
by me in the niceties of old wahs, who wanted to price it higher or
sell it on eBay. Heh.

[Loeslin]

"57chevy" <no...@home.net> wrote in message news:<Pxx9a.15699$dO.1...@fe05.atl2.webusenet.com>...

That resistor (33k/100k) is very important to the wah-wah sound. It
limits the "Q" of the filter. The lower value (33k) will have less
resonance. The effect depends on the quality of the inductor etc. but
it does have an effect. In 1974 I put a 500k ohm potentiometer with a
10k resistor in series to replace this resistor (33k in my Sepulveda
Cry Baby) making it variable from 500k to 10k (instead of 33k). At the
time, I did not know about the 100k in the old pedals. I also reduced
the 470 ohm resistor to 270/330 ohms and "decoupled" the output to get
a huge frequency sweep range (need to be careful here, this can
actually make the pedal oscillate on its own). Higher "Q" also makes
it sound like a little more "sweep" range but they are not the same.

Anyway back to the 100k ohm resistor - the old carbon composition
resistors would absorb moisture over time and, IIRC, they would drift
out of tolerance to over 1 Meg ohm making the resonance even higher
(effectively removing the resistor). All you had to do was bake out
the resistors for a period of time to remove the moisture but somehow
I never heard of anyone "baking" their wah pedals out to get the
original sound back, however, I did hear from people that the older
ones sounded better ;-)

I hope this helps in some way.
Cheers,
Clifford