Touching up a Colorsound Supa Wah

[mrsuspend]

A friend gave me a Colorsound Supa Wah to restore, actually it's in pretty good shape for being 33 years old!
It doesn't have the famous Colorswound sweep though, sounds a bit weak although the general volume is fine.
Would a change of electrolytic cap be the first to try or should I look at some other component(s)?

Also, what do you replace that awful old foam rubber with?

Thanks!

/Magnus

[joegagan]

looks cool! is this the same one i saw on facebook a few months back?

i agree, changing the electro cap in a pedal this old is a good place to start. also, verify that the pot is correct, the issue you refer to could be a wrong value or poorly adjusted pot. i have seen many vintage wahs with replaced pots that were just plain wrong. what were these people thinking?

( two weeks ago i a restored a beat up old thomas wah from around 1974 that had a correct looking pot. on further inspection , i found it had a date code of 69, was  100k but linear instead of audio taper. and it was scratchy of course.)

[mrsuspend]

I don't think this one's been on Facebook, it's been on top of my piano waiting for me to get some free time 
Thanks, I'll have a look at the pot as well!

/Magnus

[Exactopposite]

I see the electrolytic is a 4.7 but I recall it being 10 uf on the schematics I've seen before. Is the Supa wah a different circuit?

[joegagan]

there were reports that the inductor could vary anywhere from 800 to 1.5 mh in these. not sure how the 4.7/10 uf cap to ground is affected by that range of inductance. there are a lot of wahs that use 10 uf.

[mrsuspend]

I see the electrolytic is a 4.7 but I recall it being 10 uf on the schematics I've seen before. Is the Supa wah a different circuit?

The 4.7 uf is very probably original, the board looks completely untouched and was covered in disintegrating foam rubber on both sides.
I've not seen a schematic of the Supa Wah but according to reports it sounds 'bigger' than the regular wahs. Simply 'Supa'!  

/Magnus

[Ronan]

What sort of transistors are in that board? And the cap in the top left corner, does it have some markings? It does look close to a standard Colorsound wah circuit but one or two resistors are different values by the looks.

[mrsuspend]

What sort of transistors are in that board? And the cap in the top left corner, does it have some markings? It does look close to a standard Colorsound wah circuit but one or two resistors are different values by the looks.

The green caps are .22 uf. The red cap reads 10K H40 74, possibly .01 uf? The transistors both read BC 184 C. The tropical fish cap has no marking but I make the colour code out to be .01uF (brown black orange black red)
/Magnus

[Ronan]

I had a Colorsound Wah/Swell at one stage, an old blue one. I traced the schem and here is the schem of the wah section of the circuit.
The differences with the Supa Wah seem to be the number of 470K and 100K resistors, I am not sure what the resistor is in the top right corner between the the tranny and the 0.22 cap, can only guess it at 100K? Also the inductor could be a different value. The inductor on my old Colorsound had about 470 turns on it, and there was not much room in the potcore for many more turns.

Thanks for the tranny numbers, seems to ring a bell. If I remember right I decreased the value of the input resistor for more output level, and decreased the value of the 0.01uF cap connected to the inductor to make it go a bit higher/thinner. The actual pot position in the metal frame is critical, if you want the sweep to go lower or higher, loosen the nut on the pot a little, and rotate the pot slightly in either direction (you need to listen to the effect to see if you are going in the right direction), and then check that the pot itself doesn't get broken  by manually moving the footpedal full travel. For example, if you want more treble (heel down) response, put the pedal in the heel down position and rotate the pot until it comes to a stop (max rotation). If you go in the toe down direction, don't forget the pedal travels an extra distance when the footswitch becomes depressed. The main thing is you want the pedal to stop moving just before the pot runs out of rotation, otherwise the pot will get broken. Once you get it set up right, then tighten the nut on the pot. You might even have to move the rack to another tooth on the pot. Take the time to set it up and it will deliver the sound you want.

Edit: I just remembered the wah/swell I had, it didn't have a rack and pinion type gear setup on it, it used a slotted nylon piece on the moving pedal connected to something like a crank pin on the pot. Due to the mechanical arrangement it was difficult to achieve a lot of pot rotation. Maybe the Supa Wah is an improvement in this area.

[mrsuspend]

The differences with the Supa Wah seem to be the number of 470K and 100K resistors, I am not sure what the resistor is in the top right corner between the the tranny and the 0.22 cap, can only guess it at 100K?

Sorry for the late response, yes it is indeed a 100K.
Well, I changed the cap, the very worn battery connector and even replaced the foam rubber as I couldn't find any other non destructive way to secure the circuit board
It sounds decidedly better now although I've yet to try it with a proper guitar amp.
The question now is should I put an [edit]DC[/edit] jack in or is that considered sacrilege?

/Magnus

[Ronan]

If you are going to drill a hole in that thin steel, be careful, it is not easy, once the drill bit bites through it can make an ugly hole and continue on into the guts of the pedal causing all sorts of unplanned damage faster than you can stop it. If you can clamp a piece of hardwood or aluminium behind the proposed hole, that will slow the drill bit down during the exit from the hole. Whether or not to do it, on one hand it is a good idea, on the other, the pedal isn't so original any more and will lose market value.

[Skruffyhound]

DC, presumably/hopefully. Typo no doubt.

[mrsuspend]

Typo! Sorry 

[Sean-SG]

Could I possibly see photos of the wiring on this pedal please.  I have one that uses the battery all the time - even when the jacks are out!

Cheers

SEAN

[mrsuspend]

Sorry Sean, this post was made 8 years ago and I no longer have the Wah. I reinstated the image in the original first post though. Never had images of the wiring since that wasn't the problem.

/Magnus

[Sean-SG]

A very kind forum member (Paul M) has sent me a schematic.  cheers Paul

To save me from going mad, could anybody with an original Colorsound Supa Wah and a digi camera, post a couple of photos of the wiring from the jacks to the PCB please?

that would be super.

Cheers

SEAN