Weak Shinei "Superfuzz" tone?

[Rodgre]

I have one of the many Shinei Superfuzz/wah pedals and it has somewhat of a weak sounding fuzztone compared to my other similar pedals. Everything works as it should, but the fuzz seems less gainy and gargantuan as my others. At first I thought the battery was dead, but it sounds the same with a brand new one.

Is there a certain place in the circuit where one could tinker to increase the gain to make it sound less anemic?

Roger

[petemoore]

Is there a certain place in the circuit where one could tinker to increase the gain to make it sound less anemic?
  Sure...take a look at the bias on any active stages.
  I'd wanna know what the gain/leakage of the transistors, then have a good look at the schematic, I'm not sure if htat's possible with the transistors in the circuit.
  Drawing out the circuit or sourcing a schematic might be.
  Determine what each stage actually does [buffer ? gain ?]...for starters, then you can use the voltage bias readings...and perhaps an audio probe could tell something about 'where it's weak where it should be strong'..and you could diddle with gain via altering the 'peripheral' of an active.
  But at that point I would consider a complete new build instead of an intrusive exploration of the original.
  Perhaps by building a strong one, then comparing to the weak one [say with bias and audio probe comparisons], the problem could be more easily identified.
  If instructions would be helpful [such as how to determine what type of active stage your'e looking at] say so.
 

[GREEN FUZ]

These voltages might make a good reference point.

http://www.diystompboxes.com/smfforum/index.php?topic=64068.0

[Rodgre]

You guys are awesome. Thanks.

I'll double-check but I think it's this version.



(edited from previous schematic)

Here's a link to a site with detailed photos.

Roger

[joegagan]

i repaired an original shin ei back in march , i thought similarly to you rodgre, i was  expecting something much more gargantuan tone-wise.

but after playing it a few minutes i realized i really liked it just the way it was. check out this video demo i did. is yours kinda mild like this one? or less fuzzy than the one in the video?

http://www.youtube.com/watch?v=ChvmvnBYG7Y

[GREEN FUZ]

So which version do you have ? The first picture you posted was the 8 transistor version, the current one has 6.

[Wounded Paw]

superfuzz and it's variants need a matched pair of transistors in the octave up section or the sound is weak.  The pair that are tied together.

[Solidhex]

These voltages might make a good reference point.

http://www.diystompboxes.com/smfforum/index.php?topic=64068.0

Yo, Yeah I posted those superfuzz voltages a while back. The 6 transistor fuzz wah is different but contains a lot of the same elements of the superfuzz circuit. I would recommend removing the 10k resistor connected to the collectors of q 3 and 4 and tune it by ear with a 10k pot with a fresh battery. There should be a sweet spot in there. Adjusting one of the 22k resistors should affect the amount of octave present. Its subtle though.

--Brad

[petemoore]

  That Puppy snarls and growls...nicely.
  Octaves can sometimes 'Bark' and shreek.
  Thanks for the informative demonstrations Joe !