Not sure what to say about this circuit. Looks like a fun preamp with a built-in speaker emulation, and it’s supposed to sound really nice. I took the liberty of simplifying the DC input circuitry a bit (the schematic called for a complete bridge rectifier). Also, the original is a buffered effect, but I tried to set this one up for true-bypass wiring instead. Hopefully it’ll work.
Update (20.12.2012): Built it tonight and it works great. I have to say this one sounds really good! Verified.
I know some of you have had problems building this so here are the voltages on my build.
Power supply: 8.89V
All pots at approx. noon, “Rock/Classic” switch set to “Classic” and the speaker emulation set to off.
| No. | IC1 | IC2 | IC3 |
|---|---|---|---|
| 1 | +4.79V | +4.72V | +4.77V |
| 2 | +4.79V | +4.73V | +4.77V |
| 3 | +4.35V | ~+3.90V | +4.74V |
| 4 | 0V | 0V | 0V |
| 5 | +4.70V | +4.78V | +4.78V |
| 6 | +4.72V | +4.78V | +4.80V |
| 7 | +4.72V | +4.79V | +4.80V |
| 8 | +8.89V | +8.89V | +8.89V |
I made two non-critical substitutions; I didn’t have any 680 ohm resistors and so used 510 ohm ones instead, and I used 220uF/25V electrolytics in place of the giant ones the original calls for.
Hi Kevin,
When it comes to the pots your guess is as good as mine. As long as you’re satisfied with the result it hardly matters 😉
Thanks for the layout, got it up and running first time and sounds great.
I built it with all linear pots first but changed them for log which seems
to work better especially as I go for lower gain stuff,I know the original
schematic by Award Session is online and shows 220kB but was wondering if
the B was the old UK mark for Log?
Anyway thanks again.
Kevin
That is some nice work, wow……
Looks great 😉
done!
http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/JD10/JD10-01.jpg
http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/JD10/JD10-02.jpg
i just built this one today and I love it. i first used all 220K linear pots as shown, but I found that log pots work better for the gain, bass and mids control so i used log pots in those positions.
And as a user for 18 years i can recommend these settings for a neutral sound: Treble-0, middle-full, bass-10 o’clock. It takes other pedals really well, try it. It really is a nice little amp in front of your amp….