Fuzz Face + Escobedo Bronx Cheer = FuzzBerry?

[Josh?]

Hey everyone! I know I've been gone for a month or two, but I finally had some time to mess around with a couple circuits, and yesterday I had an idea to combine Tim Escobedo's Bronx Cheer (http://www.diale.org/escobedo.html) with a fuzz face.  Here's a diagram I quickly whipped up to show you guys:



*The larger this resistor is, the less raspberry-like the fuzz is. Any value works fine, but I may make it lower than 68k.
**This is actually a 100k trimpot, but I think 82k is close enough.

I've tried replacing either transistor with a bronx cheer-like setup, and I prefer this one better. I think it sounds pretty cool on bass (like a cross between a regular fuzz and the bronx cheer), but it's a bit lacking on guitar, especially at lower gain settings, which is fine by me, cause I'm mostly a bassist. The Bronx Cheer part of it sounds a lot better with my tone knob all the way down, for some reason.

Right now it's just on a breadboard, and I'd love to hear any advice y'all have. Thanks!

[rankot]

Looks promising!

[sergiomr706]

Great idea! Did you notice some bass frequencies lost? Input cap is 100n I tell you that  because lots of fuzzes changed to fuzz Ive seen, they had upped the input cap to 470n or 1uF

[antonis]

Nice ..!! 

(I'd also try to bias BC184 with a singe resistor and place a cap in series with 47k feedback resistor - just because..  )

[duck_arse]

hmmm. any idea the hFE of your BC184?

[antonis]

hmmm. any idea the hFE of your BC184?

Absolutely none..!! 

(any idea, even the slighest one, about the transistor(s) h_FE on a Fuzzy circuit, simply kills imagination for the result..) 

[turdadactyl]

Let's hear it!

[Josh?]

Did you notice some bass frequencies lost?

I didn't notice any low-end loss, but I wasn't listening super closely for it. It certainly adds a ton of higher frequencies, and making the caps around the MPSA13 larger tames that, but loses a bit of the sound of the original Bronx Cheer. When I have time to test a larger input cap i'll let you know.

I'd also try to bias BC184 with a singe resistor and place a cap in series with 47k feedback resistor

Can I ask why you'd recommend both of these things? I'm interested in learning more about the science behind the things I'm building.

hmmm. any idea the hFE of your BC184?

I'm not sure, but I know it has a relatively low hFE. Honestly, I just chose it because, in my very limited experience, they sound good with my bass. I do want to learn more, though, so why'd you ask?

Let's hear it!

Unfortunately, I'm pretty busy with Thanksgiving and all, but I'll try to record it sometime this week. Thanks for being interested!

[antonis]

I'd also try to bias BC184 with a singe resistor and place a cap in series with 47k feedback resistor

Can I ask why you'd recommend both of these things? I'm interested in learning more about the science behind the things I'm building.

You omited " - just because.." on your quotation ..

I'm not fan of negative feedback bias (DC) for reasons beyond of present discussion but, in breef, it's more wise to have a more "steady" bias (in the degree of a single resistor bias configuration could be considered more steady than a NFB one)..
(MPSA13 is a very high DC gain device with almost unpredictable DC Emitter current/voltage.. Multiplying that with BC184 wide DC gain spread you can easily jump into muddy waters trying to find out the reason for Gain pot not overal pesponce - to name an imaginary issue..)
So, placing a series cap to 47k feedback resistor you "cut off" DC feedback but you keep the benefits of AC NFB..

[duck_arse]

hmmm. any idea the hFE of your BC184?

I'm not sure, but I know it has a relatively low hFE. Honestly, I just chose it because, in my very limited experience, they sound good with my bass. I do want to learn more, though, so why'd you ask?

...... and ........

hmmm. any idea the hFE of your BC184?

Absolutely none..!! 

(any idea, even the slighest one, about the transistor(s) h_FE on a Fuzzy circuit, simply kills imagination for the result..) 

I have recently been given some vrr low gain 2N2369's [thanks B.O.S.], and have been looking for something fuzz to build with them, something not a fuzzface, something I haven't built before, to fit a nearly ready box, max 3 knobs, no switches. when I saw the darlington I thought they might fit the bill, because, as the old saying goes ....

if you can't beta 'em, join 'em.

but - I couldn't get the bronx to raspberry in the first inst, and couldn't wangle the fuzzberry to bronx either.

[antonis]

if you can't beta 'em, join 'em.

As far as that  &%$%*& intrinsic emitter resistor r_e doesn't intrude to spoil  your joint..