Dist+ germanium si questions.

[BillyJ]

I was swapping diodes last night and it seemed to me that only the germanium diodes would clip.
Any Si ones I put in there never seemed to change the sound at all.
Is this possible this circuit is just not putting out enough to drive Si diodes?It sounds really good with the germanium diodes just not loud enough.
I may try changing the pot to change the volume but want to be sure there isn't something else wrong first.
Is there a way to check if the diodes are clipping there thing in the circuit?
I guess I could try and listen in with an audio probe?
If they aren't conducting do I have a problem?
Thanks for any help.

[petemoore59]

I play loud note with one hand, pull diode out with other, play loud note, put diode in...listen for difference...then same as above except boost tar of the input with booster ckt. [more than I would usually use] for al intended purposes if I cant' hear clipping differences now, they don't matter because I can't.  [sometimes the diode clipping difference can seem subtle...especially if they're not getting 'pushed hard past threshold...[nomenclature?].

[RDV]

If there is no clipping with Si diodes then you have wiring problem cause I just built one and used 1N4148s first, and then LEDs second; both clipped like crazy, just a bit raunchy though. I stuck with two different LEDs for a bit of assemetry, and use it as an OD, turning the volume all the way up and just bring the gain up till I've got the level I want, really works nice with the distorto channel on the Marshall.

Regards

RDV

[Joep]

me too, even with red leds.

You may have a problem in the circuit.

R6 + R7 (Dist pot)  and R8 determine the gain of the circuit. Check if you got the right values here. Check also R9 the output resistor, for the right value.

I'm referring to Tonepad's project PDF (rev 2, 4 march 2002)

Hope this helps.

Joep

[BillyJ]

Cool I will take a look. Say is there a way to check if the diodes are clipping while in the circuit?
I tried to listen in with the audio probe as I am sure I have listened to clipped signal before somewhere but this did not work this time.
I will take a long gander at my wiring and such but I am pretty confident the layout is correct.
I will chack values as I think I could mess that up easy enough.
I really think it is working right and may be clipping with the Si and LED but I just can't hear it throught the poopy battery amp I have here. I would bring stuff along to rehearsal but people get pissy if I spend their time diddling inside a box :O)

If anyone knows a test please lay it on me. I will poke around the FAQs and such cause itis proabably right there.
Thanks everyone for the patience and the help!!

[RDV]

Without the diode clipping, it will only act as a clean boost for the most part, also diode polarity is everything.

Regards

RDV

[BillyJ]

Without any diodes it is way louder but not exactly clean...
I am pretty sure I have the polarity down as the germaniums seem to do a lot of clipping. Unless they are labeled incorrectly. I will test them.
Shoot I have some other things to mess with at the moment but I will try a headphone amp I have that should let me listen in better.
Like I said maybe it is working and I just can't hear it.
Thanks for the input everyone.