Dead end FX Oiolosse (Holy Mountain) question

[Kroars]

I recently built my first Dead End FX pedal (built tons of PedalPCB and Aion) and I'm not sure if the off board wiring is correct.  Build docs are pretty good, but I wonder if I somehow screwed up the 3pdt switch.  Basically it seems to work fine (all knobs function well and effect circuit) although LED is only dim when in bypass but bright when effect is activated.  Maybe that's how it's supposed to work? Also, while there definitely is a good amount of gain/distortion it does feel a bit weak in that dept, again maybe that's just the circuit.  Curious if anyone else has built one?  I've not played with the original Midnight Amplification Holy Mountain but based off of YouTube demos mine seems like it could definitely use a bit more gain....and the led issue.

All parts pre-tested prior to installation and j-fets biased to 4.5v although I did have to use a 500k trimpot on Q1 to be able to reach 4.5v.  All others are 100k as per build doc.

Thank you for any help you can provide!

Thanks I'm advance.






Oiolosse build doc:
https://drive.google.com/file/d/1ddkG_90f9YdqizsWHmSlZKDCZyQZIlEX/view

[ElectricDruid]

Your bypass switch wiring looks to be right from the photos. What's the solder-side look like? Could there be a bit of something causing a short and keeping the LED on?

For the sonic problems, I see a lot of trims that presumably need to be set up correctly so I can see a virtually infinite number of ways to do it wrong! Still, turning the trimmers till you get 4.5V at the drain doesn't seem too difficult. You say that you had to use a 500K trimmer to get Q1 to bias correctly. That sounds suspicious to me, and I'd rather find out what's wrong and why it doesn't bias right, rather than "fix" it by increasing the trim value. Maybe R4 and R5 are the wrong way around? (similar colours).

[Kroars]

Thanks for clarifying the bypass wiring.  I thought it was correct as well, but verification is nice. Looking to see if anything was touching was my next step, although I thought maybe just maybe the LES was supposed to be on all the time (going from dim when bypassed and bright when activated) in this circuit.  As I said, when bypassed the LED is on but dim (maybe 50% brightness).  When effect is activated LED becomes bright (100% brightness).  Since it's my first DeadEndFX board I wanted to double check before dismantling.

The board does call for 3296 style trimmers and I used sockets with 3362's although that shouldn't be an issue.  I agree that the fact that I had to use a 500k trimpot for Q1 to reach 4.5v while all others were ok reaching 4.5v with 100k trimmer is strange.  R4 & R5 are 220k & 2k2 and are in their respective positions (just double checked).  Perhaps I should swap out the Q1, although I did pre-test before installation and the SMD versions do seem to be a lot more reliable than their through hole counterparts (at least with J201 as of late).

Maybe the pedal sounds like it's supposed to.  I just felt the YouTube demos did seem to have a bit more gain/dirt. 

The LED is what's really throwing me off.  I do have another one nearly done. I build to of the same pedals at once both because it's efficient and it does help identifying an issue if one sounds different than the other (aside of course from germanium fuzz and the like).  I'll finish that one up as well, just needs to be wired, and see if there's a difference.

Anyway, thanks again for your help!  If you think of anything else please let me know

[ElectricDruid]

I thought maybe just maybe the LES was supposed to be on all the time (going from dim when bypassed and bright when activated) in this circuit.

No, definitely not. The schematic is pretty clear that the LED is switched on when the effect is on and off otherwise. Something is shorting it somehow, or the switch is bad.

Maybe the pedal sounds like it's supposed to.  I just felt the YouTube demos did seem to have a bit more gain/dirt. 

Maybe, but I doubt it. You've got something fishy going on with the first stage (needs 500K to bias correctly) so that's going to throw everything else out all the way down the signal path.

Good luck with the other one. Doing two together is a great idea from a debugging point of view!

[antonis]

What is the purpose of R2 (1M) in the absence of input coupling capacitor..??

Also, IMHO, R4 & R13 220k bias resistors could be of higher value (for less signal attenuation..) and Gain pot could have a "stopper" resistor (100k or so) between lug1 & GND 'cause a "silence de mort" chain engaged effect is useless..
(unless, of course, you wish for a noisy mute effect..)

P.S.
If you want more "gain/dirt" for mid/low frequencies, make C2 (470nF) bigger..
(for high frequencies, make it lower..)

For an absolutely filthy gain, shunt R13 (Q4 Source 1k resistor) to GND with a 10μF - 47μF cap..