Foxx tone Machine pedalpcb d9b ok?

[paulbarrette]

I am looking for germanium diodes for a foxx Tone Machine build. Pedal pcb has d9b

D9B Germanium Diode - PedalPCB.com

Germanium Diode

www.pedalpcb.com

Are they ok for build?

Thanks
Pb

 

[ianmarks]

I don't think the fv is that far off from the 1n34, so should be just fine. What you might pay more attention to is matching the first pair (their fv) as closely as possible. This will help create a more pronounced octave effect.

 

[paulbarrette]

probably.
i'd get them anyway, it's good to try out different diodes and see what you like the sound of best.

diode selection in a hard or soft clipping arrangement - is really not that crucial.
(unless you're one of those special characters that insists on having the exact same components as a genuine original)
you could use 1N4148 diodes and it would probably still sound great.

true. They are not expensive. It is worth a shot.

Thanks

Pb

 

[paulbarrette]

I don't think the fv is that far off from the 1n34, so should be just fine. What you might pay more attention to is matching the first pair (their fv) as closely as possible. This will help create a more pronounced octave effect.

Good point. I better order extra to compare and get a good match

Thanks
Pb

 

[Coda]

If you like to live life on the edge, then yes…

 

[airbud]

I don't think the fv is that far off from the 1n34, so should be just fine. What you might pay more attention to is matching the first pair (their fv) as closely as possible. This will help create a more pronounced octave effect.

ah i will go back and match the diodes i have in the octaclang... thanks!

 

[Feral Feline]

Stick 'm on a switch with a matched pair of Schottky on the other side of the switch to compare...

 

[PedalBuilder]

D9B (or any other D9x diode) should work fine. If you want a more pronounced octave, use lower vf diodes for D2 and D3 (the hard clipping diodes). This is also the case for the Super Fuzz and other octave fuzzes that use hard clipping diodes.

 

[paulbarrette]

Stick 'm on a switch with a matched pair of Schottky on the other side of the switch to compare...

Sounds good. I have some snap off sockets i can use.

Thanks
Pb

 

[paulbarrette]

D9B (or any other D9x diode) should work fine. If you want a more pronounced octave, use lower vf diodes for D2 and D3 (the hard clipping diodes). This is also the case for the Super Fuzz and other octave fuzzes that use hard clipping diodes.

Thanks. I will order some extra to compare

Pb

 

[owlexifry]

D9B (or any other D9x diode) should work fine. If you want a more pronounced octave, use lower vf diodes for D2 and D3 (the hard clipping diodes). This is also the case for the Super Fuzz and other octave fuzzes that use hard clipping diodes.

so you're saying on my superfuzz build if I used lower vf clipping diodes, the octave effect becomes even more pronounced?

considering the octave effect is dependent on expander / gain control - i always assumed it was just about more signal getting to the octave stage..
or is there more of a direct relationship between the clipping diodes and octave effect?

for best octave i just matched a pair of 3904s for these guys (dunno what the ref no.s are):

 

[PedalBuilder]

so you're saying on my superfuzz build if I used lower vf clipping diodes, the octave effect becomes even more pronounced?

considering the octave effect is dependent on expander / gain control - i always assumed it was just about more signal getting to the octave stage..
or is there more of a direct relationship between the clipping diodes and octave effect?

for best octave i just matched a pair of 3904s for these guys (dunno what the ref no.s are):
View attachment 73722

Correct. Matching the transistors in the differential pair (I like to match on both hFE and Vbe) is essential to getting a strong octave effect. Using low Vf diodes will increase compression and distortion, which makes the octave seem more pronounced. I breadboarded the circuit a while back and experimented with using 1N914 and LEDs, which made the output signal louder but made the octave a lot less noticeable. Switching to D310 diodes (Vf ~180mV on my Fluke) cut down on the volume significantly, but really helped the octave stand out. I’d also recommend changing the bias resistors on the last gain stage to increase the output level if you use very low Vf diodes. I posted my preferred Super Fuzz output stage bias scheme here in case you’re curious.

Breadboard it and see what you like!

 

[bean]

For the rectifier diodes, you want something with a VF as close to 0.33v as possible. You can use BAT46 Schottky diodes as a sub which are 0.35v. Once you get into higher VF, the effect may not work correctly. I tried D9E recently which have a VF of 0.45v and they did not work at all!

For the clipping diodes there is more leeway, so higher VF in not a circuit breaker.

 

[paulbarrette]

Wow that is interesting. I ended up ordering from amplified parts.

https://www.amplifiedparts.com/products/diode-1n34a-germanium

He has some 1n34a i hope they are legit. I ordered extra to compare. Hope there are at least 2 suitable. Now i just have to get some red flocking material to cover the enclosure.
Thanks
Pb