piggybacked Shin Ei fuzz

[kvb]

This has been in my gallery for nearly a year.
I have not posted about it because I have not got the sound clips.
I am posting this now because Gus mentioned not seeing many "piggyback" posts recently.

All I can say is that I built this during a breadboarding fuzz frenzy, and it was the "best."

It has the ability to be an all out fuzz monster, but it has a graceful decay. The buzz fades without an annoying zzzzip.
I think this is because of the phase dual between the output of the two transistors. It also is very quiet for being such a high gain sound.



I imagine that an NPN version with the 2N5089 would sound good too.

[Mark Hammer]

Interesting.  the Scoop pot can actually be dropped to 5k without much audible impact on the functionality of the control.

[kvb]

yeah, I used a high value just to be sure that the scoop was as removed as possible. as it is, there is plenty of noticeable change in most of the pot's rotation

[Gus]

Good to see a different take on an effect.

[gigimarga]

Which are the voltages of the transistors for your schematic?
I am very curious about these voltages (best from an original...) because i've built one using GGG's and i can't obtain more than 3.5V on Q2's collector (in GGG's papers wrote that it must to be 6.6V!!!)

[Toney]

I love this circuit too.
I was looking at mine just this week...might be time for another take on it.

Regarding the emitter resistors, is it 4k7 on Q1 and 47K on Q2 as per the schem?
Confirming in case of typos.

[kvb]

I will try to remember to take some measurements, but it might take me some time to post them.

All of the values shown are correct. My only typo was writing "phase dual" instead of phase duel. 

One might think that the 47K at Q2 would stop the piggyback effect, all I can say is that it does "something."

The one component that seemed to be a tweeking point to get or tame some harshness is the 18K at the top.

I doubt that this sounds like an original because I can't describe it as "sick" - it sounds sweet.
The range of distortion available with a turn of the guitar's vol knob is huge.
If you build it with a set scoop (no knob) - you might want a volume recovery stage.
with the scoop out of the circuit this thing is loud.

And as much as I enjoy the thought of having a one of a kind effect - I hope y'all build one too.