After Josh Homme revealed one of his secret weapons, the small Peavy Decade amp, prices on those sky rocketed tenfold. Deadend Fx just released thier Dekandent project which is based on the preamp section. Not sure how close you'll get to the QOTSA tone but it is at least a piece of the puzzle.
Schematic is avaiable HERE
Built. Ground wasn't labeled so I just connected one to M23 (next to Bass 2&3). Everything seems to be working except that it sounds a little weird when the Saturation is switched off. Almost like it's passing a clean signal with just a tiny bit of the OD/Sat sound? Could be a mistake in my build--haven't had a chance to check it over fully. I did compare the layout against the schematic and didn't catch any mistakes. So with that one caveat about the Sat switch, I think it's safe to verify this one.
ReplyDeleteOh! and I only noticed 36 cuts on the board. but I could just be missing one somewhere.
DeleteI've tagged it as verified despite the caveat. haven't heard any sound demos of it so I'm not sure how the clean channel is supposed to behave.
DeleteOh, and it is 36 cuts indeed...
Thanks for giving it a go!
awesome! thanks for the layout :)
DeleteHere's a video of this pedal: https://www.youtube.com/watch?v=C3p-YaQO-04, seems to have decent amount of gain gain on the normal channel, so maybe something is wrong
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DeleteHi Felipe,
DeleteThe Decade in the video is made with the DeadEnd FX's PCB and not with the layout from here (I forgot to mention that in the video description, it's fixed now).
The Clean channel is mostly clean in the low Gain settings, and that's something I forgot to show :)
Cheers,
Dronechov
Hi Donchov, just passing here and totally missed your post! Thanks for clarifying, cheers!
DeleteHi, there's an update at the schematic, they recommend to increase R26 from 33k to 150k and also noticed that it should be parallel to the 100pf cap at pins 1 and 2 of the IC1. In the layout is touching pins 2 and 3.
ReplyDeleteThanks for the heads up. Increased the 33k to 150k. Not sure about the 100pF cap though. I assume you mean C26? If so, it is there, across pin 6 and 7.
DeleteHi fuzzhead!🤔I think you update R11 instead of R26. What I wanted to say in the previous comment is that R26 should be parallel to C26 on pins 1 and 2 of IC1 but in the layout R26 is touching pins 2 and 3.
DeleteA dual op amp have two identical channels which are interchangable. (pin 123,567) You can mix them up with no change in functionality. This is the case here. Just ignore the pin numbers and focus on the schematic symbols.
DeleteWith that in mind I see no errors in the layout. Sometimes I swap the order of the channels just to make the layout more compact and/or to make it "flow" easier.
Ok I see... thanks for the info 🙂👌
DeleteIn reviewing the schem the ground pad should be 1D, not 1C
ReplyDeleteRegarding on the ground on ic2 pin2,are they same ground connected to ic1 pin 4?
ReplyDeleteThere is no ground connection at pin 2 of IC2. Ground is connected to pin 3. And yes, it is connected to pin 4 of IC1
DeleteCorrect, so the ground wire should be moved down one row in the layout.
DeleteTnx sir fuzzhead.more power!
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ReplyDeleteUsing spdt (on/on) sw.from input jack soldered to sw2 pin,sw1pin to pcb input label and lastly sw3 pin to sat sw2..just my thoughts based on peavy schem.
DeleteNow just realize that the tranny got no audio passing it.
ReplyDeleteIts just a kinda switch on and off for that op amp!
Success!i just built and it has a very identical sound output with the original peavy.verified!
ReplyDeleteLastly, i used 5532 chip for the op amp.its kickin loud!
ReplyDelete