recommended Hfe's for RM Axis Fuzz??

[hellwood]

ive tried a few combos out, but nothing is even close to blowing my mind. the only info i can find is about recommended transistors [which when tested range from 79-700 Hfe (5089, 3906, 3904)] , so thats not really helpful. i even tried a germanium for Q1 and it was depressing!
as far as biasing, things look normal (a little low). Hfe's anyone?

[swt]

use motorola 2n3904 and 3906. This is what he used. They bias perfectly, no matter what, and also give you the right sound.

[tcobretti]

I would measure some HFEs and try some different combos to see what happens.  I have found the different transistor values to have very little effect in this circuit, with the exception of very low HFEs.

[brett]

Hi
the original hFEs would have been around 200.
If I recall correctly, the hFE of Q2 is less important than the hFE of Q1.
As noted above, 2N3904s and 2N3906s are useful, but modern ones have much higher hFE (300 to 400) than old ones (200 to 250).
Maybe try a BC107 for the 2N3904.
Generally, this circuit is considered very good.
cheers

[tcobretti]

People either love this one or hate it.  It has a lot to do with your rig.  It sounds great with darker amps, but kinda bright with SS or Fender amps.

[hellwood]

OK! i have found the top secret tranny combo and this thing scorches! my original Hfe's were Q1/Q2 - 171/147. w/ Q1 any lower, well, it basically sucked! BAD! next, i tried a Q2 of 255. this alone made this pedal come alive w/ a gritty and grindy tone that will make any axis fuzz hater shut the f*** up in a hurry. it did have somewhat a lack of sustain (which is a compromise i deal w/). then i stepped up Q1 to 195 and things got worse, so back to 171. finally Q2 at 540 and this thing was LOUD and screamed like a mad bitch and sustained forever, but lacked the gut-bucket tone i always need, so...Q1/Q2 - 171/255 and its goin in the box! thanks for the suggestions!

[momiel]

What schematic did you use?

[Jackie Treehorn]

I tried a LOT of different 3904's and 3906's.  Ended up with 195 for the 3906 and 282 for the 3904.  Similar to what you ended up with, too.

[hellwood]

What schematic did you use?

this one:
http://fuzzcentral.ssguitar.com/schematics/axisfuzzschem.gif

I tried a LOT of different 3904's and 3906's.  Ended up with 195 for the 3906 and 282 for the 3904.  Similar to what you ended up with, too.

yeah! your ears must be similar to mine and im guessing you are happy w/ your results also?

[momiel]

What schematic did you use?

this one:
http://fuzzcentral.ssguitar.com/schematics/axisfuzzschem.gif

I tried a LOT of different 3904's and 3906's.  Ended up with 195 for the 3906 and 282 for the 3904.  Similar to what you ended up with, too.

yeah! your ears must be similar to mine and im guessing you are happy w/ your results also?

Thanks

[STOMPmole]

People either love this one or hate it.  It has a lot to do with your rig.  It sounds great with darker amps, but kinda bright with SS or Fender amps.

I've got one (an actual non-clone RM) and I'd have to agree with your statement 100%.  It sounds pretty cool through a cranked Marshall or any somewhat full/dark sounding amp like a tweed Fender Deluxe, etc.  Play it through a black/silver Fender and it's complete crud.  A SS amp would be intolerable