Wah ... Build or rebuild?

[Mordred]

I finally got myself a crybaby (ebay for £30  ). The model number is GCB-95.. and the date on the board is 12-8-94 and the revision is G.
There is a bit of a downside, it works great but when the wah is switched on for use, the sound loses all the bass and mid tones, all that comes through is trebble.

Rather that starting to mod the wah, I was thinking about building a replacment on perf board and installing into the chassis.

Before I start on this, has anyone encountered a problem of this nature or if builing or modding would be the better option?

Thanks in advance for any assistance.

[petemoore]

  The first thing I'd try is adjusting the gear range more towards 'toe down'.
  Push the wah toe down, Open the back, loosen the 'straight gear's' screw/push plate, pull the rack back from the round gear, rotate the gear in the direction of toe down a cog or two, reassemble and try it out, re-adjust if necessary.
  Try that and see...

[tcobretti]

Does the sound change at all when you move the pedal?  I agree with Pete, it sounds like the problem is with the rack and pinion that spin the pot.  I believe you can buy them from Dunlop if they need to be replaced.

[petemoore]

  Perhpas I explain better.
  The gearing range ofthe gears provides less rotation than the pot can do, you don't want the gear and pot to be what stops the treadle.
   but adjusting the gear so it turns the pot farther toward the bass side could be all it needs to adjust some of the treble off, the near/toe down settings, with the treadle all the way to the mechanical stop @ toe down, the pot is turned to a notch or two 'less' in that direction, because you've skipped a cog or two.
  Again you want the mechanical treadle limit stop [bumper between treadle pedal and bottom case], NoT the limit of the pot through the gear assembly...

[Paul Marossy]

+1 on checking the pot rotation setting.

[Mordred]

Thanks for the replies.
Yes, the wah works as it's supposed to... it wah's

When is it switched off the sound is absolutly fine, as soon as it's switch it on the mid and bass drops out regardless of what position the pedal is at.

I'll try out your suggestions when I get home from work tomorrow. It's a bit late and I'm feeling tired now.

Thanks again and I'll keep you posted.

[Paul Marossy]

If it "wahs", then the inductor must not be the culprit. I think that maybe it's miswired. Rotating the pot should definitely do more than accenting all of the high frequencies. Is it hard wired, or does it have a quick disconnect wiring harness?

[Mordred]

Here are pics of the CB

[Paul Marossy]

The pics aren't showing up... 

[Mordred]

That's just bizarre ... the were working earlier.....

Here is the link to them anyway....
    http://uk.pg.photos.yahoo.com/ph/alln_jedi/album?.dir=3989re2&.src=ph&store=&prodid=&.done=http%3a//uk.photos.yahoo.com/ph//my_photos

[Paul Marossy]

That's just bizarre ... the were working earlier.....

Probably some measure to conserve bandwidth. OK, looks like you have the newer version of the GCB-95, where everything is on a PCB with no hard wiring. Gee, I should have read that you have Rev. G - that would have told me. Sorry about that.

Anyhow, that's a strange problem that you have. It still sounds to me like the pot is miswired. Verify that the connections on your pot are correct. The wiper should be connected to the 0.22uF cap, one end to the other 0.22uF cap, and the other end to ground.

[Johan]

unlike most others I love my stock GCB-95..the trick is in how you use it. if you have a lespaul type guitar, try it with the pickup selector in the midle/both position..thats where it likes to sit..no need to mod..if you use it wit only one pickup, it will be thin on the bridge pickup and loose all volume an sound dull on the neck pickup..but when both pickups are used it's as full and fatsounding as you could ever want..

johan