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Showoff!

Digging up this thread again.

How about a version of the Blackout Effectors Mantra? Especially now that Blackout seems to be out of business.
Never seen a DIY version of this, although it was quite popular some years ago. It's a high gain overdrive with a lot of hair:

"Equally capable of invoking the sacred sounds of a classically refined overdrive AND summoning wickedly raunchy drive, with more crunch on tap than the overdrive moniker usually entails. With such a wide palette of tones and character the MANTRA will feel just as at home at the feet of the stalwart blues crowd as it will the quintessential rock & roll protagonists.
The MANTRA utilizes amp-like circuit architecture, with multiple cascaded MOSFET and JFET gain stages to insure the most natural, touch-sensitive overdrive conditions possible and a seemingly endless range of clean-up with your guitar"s volume knob. We burned a lot of midnight oil to make sure that the MANTRA could get down with vintage-type, low output single coils and hot humbucker pickups alike. From gently fingerpicked melodic phrases to bludgeoning riffs that you"ll want to play over and over and over..."

Schematic etc.: http://revolutiondeux.blogspot.com/2012/07/blackout-effectors-mantra-overdrive.html

There was a version available with a Low Gain Switch which bypassed a gain stage. I can't find a schematic for that though ....

On the Projects page in the top left corner you'll find "Archives".
http://www.madbeanpedals.com/projects/archives/index.html
It's in the "Sunking" zip.

Rej had a few tough spots. Only uphill from here.
Get well!

Runoffgroove Big Daddy?
http://www.runoffgroove.com/grace.html
(Chunky High Gain Distortion, very few parts)
(LM386 based, though)

http://tagboardeffects.blogspot.com/2013/01/runoffgroove-big-daddy.html

https://www.newschannel5.com/news/gibson-shifts-from-confrontation-to-collaboration-with-gibson-authorized-partnership-program

looks like the schottky diodes have a Vf between .55 V to .875 V ... you could double those up, go with 2N7000 +bat41 pairs, or  3mm LEDs if you want more volume and less clipping ... of those choices, I think the MOSFET would be smoother and more amp-like
if you want more clipping you could go with 1n400x rectifier diodes, bat41, or germanium ... I think the germanium sound better, even if doubled up for a more reasonable Vf.
now I kinda want to build this thing with mosfet clipping ... damn it, another project

Great, thanks! That's a good starting point.

Build it, it's worth it!

Thanks. Which type of diodes would be a good start?

The Runoffgroove Ginger is intended to be an Ampeg in a Box, primarily for Bass, but this pedal has been on my board for years, I love it, it's perfect for guitar! Thick yet open, dynamic, super effective Tone control.
The one thing though: it could have a bit more gain. I always have to hit it with a booster.

Mine is built on a TH custom board, but you can get them from Fuzzdog, OSH Park, and other places.
http://diy.thcustom.com/shop/rog-ginger-v1-0-pcb/
The TH Custom doc says: "The original circuit features 1N5818 diodes for D6/D7. I have fun listening to it with the same red LEDs in this place."
Mine does, indeed, have 1N5818 in D6/D7. Does this affect gain much?

Question: What could I do to squeeze a bit more drive out of that pedal without it changing its character at all?

Thanks!

I was feeling like it, so I made a 2 layer pcb for this suitable for 1590a. it's available via oshpark here:
https://oshpark.com/projects/zKa4A1JP

if anyone verifies the layout please let me know.

I ordered your board, verified!

https://www.gearnews.com/dean-guitars-alleges-gibson-threatened-dealers-over-copyrights/

(I wanted to post this in Tech Help, but since it doesn't concern any Madbean projects I'm posting it here. I hope that's ok)

I hadn't built any pedal in about two years but recently the bug bit me again and I built some fuzzes. And unlike before they all work.

I have a weird issue with these two, though. Clones of the Analogman Astrotone and the KMA Fuzzly Bear, both built on Fuzzdog PCBs:
https://shop.pedalparts.co.uk/AstroTone_Fuzz_-_Sam_Ash_Fuzzz_Box/p847124_8861948.aspx
https://shop.pedalparts.co.uk/Ursa_Fuzz/p847124_19816586.aspx
BOMs are on these sites.

When I crank the gain they both sound weird, the sound cuts out, farts and splutters. Roll back the gain just a tad and they both sound fine. It's just that last millimetre on the gain pot.

The power capacitor on both these pedals is 47uF. I upped it to 100 on both but with no effect.
I checked all the values I used and they are correct. I reflowed all solder joints.
What else could I do? Any ideas of what this could be?

(That KMA Fuzzly Bear is one amazing Fuzz btw)

Thank you!

Oh dear. So sorry to hear.

So, there are a couple mods I did on this circuit to try and squeeze as much gain as possible out of it. But, it seems like I went too far. The two changes are in the first and second gain stages.

To eliminate the problem try reducing R8 from 270k to 220k. If that solves the motorboating stop there. If not, either 1) replace R16 with 150k or 2) change the Gain pot to 100kB and remove (or clip one lead) of R16.

My apologies for the hassle. Please let me know what you find and I will update the build doc accordingly.

After a long time I finally did this and am happy to report that lowering R8 from 270 to 220k did the trick, the oscillation is gone!