Modding a Danelectro French Toast Octave Distortion

[veronica 1965]

Hi!
I would like to modify this Dano mini-pedal by adding a germanium transistor. I can't seem to find any schematics on this pedal online. There seem to be two main transistors, one between the in and out jacks and one just to the left of the footswitch. Does anyone know which one of these (or both) have to do with the tone? Any help would be greatly appreciated. Thanks!

[LucifersTrip]

I believe that's a clone or near clone of the Foxx Tone Machine

http://www.tdpri.com/forum/archive/index.php/t-192289.html

[Mark Hammer]

Hi!
I would like to modify this Dano mini-pedal by adding a germanium transistor. I can't seem to find any schematics on this pedal online. There seem to be two main transistors, one between the in and out jacks and one just to the left of the footswitch. Does anyone know which one of these (or both) have to do with the tone? Any help would be greatly appreciated. Thanks!

Why do you want to do this?  Is this just an "I wonder if..." experiment, or did you have some specific expectations?

[veronica 1965]

I'm trying to cheaply get a more vintage tone. from what I'm led to understand, germanium transistors were commonly used in '60s fuzz boxes and have a warmer tone.

[veronica 1965]

yes, it is supposed to be a clone of the Foxx pedal. Thanks for the schematic! The original seems to have four transistors and this only has two. I suppose I should replace both of them.

[Mark Hammer]

1) The French Toast /Foxx IS a 60's pedal.  It IS vintage tone.  It's a bit like saying "I want my 1948 DeSoto to be more vintage".

2) The distortion in that pedal is produced by diodes and by frequency doubling.  Change in transistor material will not alter that.

3) In fuzzes that DO employ germanium transistors, the design of the circuit complements how those particular transistors function.  You can't just stick a Volkswagon engine in a Honda.  The car has to be designed in concert with the engine.  Similarly the transistor and circuit go together.  The transistor does not have a "sound" independent of the circuit designed around it.

4) Personally, I think the Foxx/French Toast is one of the very best octave fuzzes around.  My only gripe with it is that the non-octave fuzz setting needs to bypass the diode. 

[Derringer]

so if you have some germanium trannies you're dying to use, I think you'd be better off just building something that requires them

or just play with some simple gain stages and see if you can get some tones that you like

that French Toast/Tone Machine was designed around silicon transistors and germanium diodes, as has been stated, changing those transistors over to germanium would make almost zero difference

and from experience, I made an octave up circuit based on the octave up section of the Tone Machine. Out of curiosity I subbed in a PNP germanium into the NPN silicon phase splitter stage while it was on the breadboard (flipped the pnp for polarity) and it made zero difference in tone

[veronica 1965]

@ Mark Thank you for the info. I'm used to modding guitars, but modding pedals is a very new field for me and my info is sketchy at best. I was thinking of making a change primarily because I found the French Toast version's fuzz rather harsh and metallic, and I thought perhaps Danelectro had taken some kind of shortcut that I could circumvent...but if it won't help then there's no point in doing it.
@ Derringer thanks for the ideas and info!

[Mark Hammer]

The Foxx/ French Toast has a terrific octave-up sound; robust, reliable.  As fuzzes go, meh. 

I've modded to "improve" it to my own tastes, by installing a 3-way switch that either removes the clipping diodes, or applies two different kinds of diode, to yield louder "rounder" distortion, or quieter harsher distortion. 

The Foxx also uses a pair of diodes to help produce the octaving.  The octave switch simply cancels the effect of one of those diodes, but leaves the other one in place, and THAT may be what is producing the harshness you note.  That particular remaining diode introduces some crossover distortion, and also chops off half the waveform.  What I've done is use a 3-positon toggle to either provide octaving (side position 1), no octaving but crossover distortion (middle position), or no octaving and no crossover distortion (side position 2).

The trouble with the French Toast, however, is that it uses surface mount construction, which makes modding tricky and not for the faint of heart.

[veronica 1965]

Yeah, I'd rather not try to change the switch....you're probably right about the diodes. I like the octave-up effect too, though. It's a good sound.