Buff n Blend issues

[Kroars]

I see there are a few folks on here that have had great success with the GPCB Buff n Blend circuit and I’m hoping someone could shed some light on this. I’m sure I’ve overlooked something.

I’ve built a Univox Super Fuzz and want to add a clean blend to it. Super Fuzz tested perfectly. Wired the Buff n Blend up to it (positive and negative from all three boards temporarily wired at dc jack) and I only get clean signal when I turn the Blend knob towards clean. When I turn it towards the Super Fuzz, it gets very quiet and I can’t hear the SF effect. I thought perhaps the SF was inverted, so I built a Stage 3 booster (as GPCB suggests for phase issues) and wired it in series with the Super Fuzz -same problem.

I have the send of the BnB going to the input of the SF, the output of the SF going to the return of the BnB. Then I tried the inserting the Stage 3 booster into the mix: BnB send going to input of the SF, output of the SF going to the input of the Stage 3 and output of the Stage 3 going into the return of the BnB. Still nothing.

Ive installed the J113 and both caps in the footswitch side of the BnB board due to space constraints. Although, both are installed in correct orientation. I can add a few more photos when I get home if needs be. I don’t suppose anyone can help point me in the correct direction.

Thank you kindly.

 

[Feral Feline]

How's this going Kroars?


I have a suggestion that's a random shot in the dark:

Splitnblend from Moonn. Does the same thing as the BuffnBlend, but with an extra JFET powering the side that would go to the Super Fuzz in your case.


Not only is that idea a shot in the dark, but I don't think it'll fix whatever may be fundamentally wrong with the build(s) — however, it may help in general 'cause 2 JFETs are better than one. Maybe.

 

[Kroars]

How's this going Kroars?


I have a suggestion that's a random shot in the dark:

Splitnblend from Moonn. Does the same thing as the BuffnBlend, but with an extra JFET powering the side that would go to the Super Fuzz in your case.


Not only is that idea a shot in the dark, but I don't think it'll fix whatever may be fundamentally wrong with the build(s) — however, it may help in general 'cause 2 JFETs are better than one. Maybe.

Thank you! I didn’t realize Moonn had one too. I love his stuff. I’ll give that a try as well. I haven’t had a chance to get back to this one. I’ve got a couple more BnB’s, figured id build a second one to see if the same problem exists. Thanks for the heads up!

 

[Anthonyj]

I've had this issue recently, I don't see if there is a led already wired into the fuzz pcb, put one in. When I tested this I noticed I wasn't getting power the effect pcb. I was able to fix the problem by jumping the sw and gnd holed on the bottom and wiring them to one of the grounds on the bnb board.

 

[Kroars]

I've had this issue recently, I don't see if there is a led already wired into the fuzz pcb, put one in. When I tested this I noticed I wasn't getting power the effect pcb. I was able to fix the problem by jumping the sw and gnd holed on the bottom and wiring them to one of the grounds on the bnb board.

Thanks for the reply. I’ve actually got 9v going into the top of the SF pcb. The 9v wire from BnB and 9v wire from SF are soldered together (temporarily) and powered.

 

[Anthonyj]

Is it working?

 

[Kroars]

Is it working?

I took a break on it. I know other people have had success with it. Although, I haven’t found anyone that has used it with a SF.