Any interesting or cool mods to the Dwarven Hammer PCB? (Precision Drive clone)

I’ve finished the Dwarven Hammer and really dig the 8 different Attack settings and am looking to build a second for our bands second guitarist. Question for the hive mind: have any of you modded the values or subbed in parts in this build? I’ve seen on the forum that some folks have subbed the 1n4148 diodes for green LEDs for a volume increase/change in clipping. Has anyone dialed in the 8 capacitor values to their liking? I’ll admit that the “attack” rotary knob at its highest setting is way too shrill with a slight decrease in volume. Maybe this would be useful for 8 strings through a dual rectifier but it’s unusable for my setup. I’m curious if anyone has any interesting mods or “improvements” on this circuit.

I play metal/grunge in drop C through a EVH 5150III for reference.
 

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If you're using it as a boost or to tighten up your amp then I found I preferred the additional headroom from LEDs so you get more boost and less of the grit, which I found undesirable for my tight metal sound personally. At the highest setting you're cutting everything below 4.8khz so I'm not surprised its shrill. You could shift all the values down one and get an extra bass setting if that would be more useful. Replacing the capacitors that go to the attack switch, replacing the 33n with a 47n and etc until you add a 1u cap where the 470n is.
 
I have built a couple of these both modded straight BOM, at the end of the day it’s a tube screamer (and I do like it… I also play a down tuned 7 through a recto 🤣) so any tube screamer mods that are out there can probably be adapted easily enough, and I completely agree with you the more extreme settings can be a little much, but after trying multiple TS variants I always seemed to get them dialed in the same way and there just wasn’t a huge difference in the useable settings for me personally, the green LEDs definitely give it a different flavor but I don’t think I would build it that way again especially it you are playing metal….. I think the “hundreds of hours” Misha put into that pedal was just chasing mod and ended right back at a TS with slightly higher gain opamp and some different cap values 🤣
 
If you're using it as a boost or to tighten up your amp then I found I preferred the additional headroom from LEDs so you get more boost and less of the grit, which I found undesirable for my tight metal sound personally. At the highest setting you're cutting everything below 4.8khz so I'm not surprised its shrill. You could shift all the values down one and get an extra bass setting if that would be more useful. Replacing the capacitors that go to the attack switch, replacing the 33n with a 47n and etc until you add a 1u cap where the 470n is.
I'm thinking this might be my next build on this circuit. Shift the values down to get an extra "Bassier" setting and adding Green LEDS instead of the 1N4148. I do use it as a boost to tighten up the amp and max out the volume with the Drive all the way down. This might be what I'm looking for.
 
I have built a couple of these both modded straight BOM, at the end of the day it’s a tube screamer (and I do like it… I also play a down tuned 7 through a recto 🤣) so any tube screamer mods that are out there can probably be adapted easily enough, and I completely agree with you the more extreme settings can be a little much, but after trying multiple TS variants I always seemed to get them dialed in the same way and there just wasn’t a huge difference in the useable settings for me personally, the green LEDs definitely give it a different flavor but I don’t think I would build it that way again especially it you are playing metal….. I think the “hundreds of hours” Misha put into that pedal was just chasing mod and ended right back at a TS with slightly higher gain opamp and some different cap values 🤣
I'm interested in subbing out for Green LEDS instead of the clipping diodes since I use it as a level boost for the 5150 along with the tightening of the bass through the attack knob. I'm curious, did the green LED swap increase the volume/headroom of the pedal? is it worth the effort is what I'm primarily wondering
 

I had to dig to find the old build report, but if you scroll down there is a sound clip of it pushing a recto, not the best but it shows it in the context of a amateur mix, and yes it gives a little volume and headroom bump compared to the diodes in the BOM and is less “compressed “, depending on what kind of sub genre you are playing it could work for metal, there really isn’t any extra effort to sub the LEDs or even to change them back really, just don’t shove the LEDs right up against the pcb and removing them would be easy even if you aren’t super confident in desoldering components.
So in short it’s a simple mod worth trying that you could easily reverse if you hated it.
 
I'm interested in subbing out for Green LEDS instead of the clipping diodes since I use it as a level boost for the 5150 along with the tightening of the bass through the attack knob. I'm curious, did the green LED swap increase the volume/headroom of the pedal? is it worth the effort is what I'm primarily wondering
if you use socket pins you can swap out clipping diodes very quickly and try and all sorts on the same build.
then you don't have to commit to any diode decisions.
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heck you could open up your current build, desolder the diodes, and put in some socket pins right now and have a clipping diode shootout extravaganza. extra points if you record the results and then play them back to yourself back-to-back for a more objective assessment of which sound you like better.

imo - green diodes not only increase output volume, as they'll clip at a higher threshold (more headroom), but they also sound much brighter.
at first i thought it was really cool, aggressive, and biting, but then when compared back to good ol silicon 419/4148, i felt it was too much, too harsh and cutting too much low end.

red diodes will give similar results (brighter, more aggressive than 4148)- but less exaggerated or intense as the green.
if you look at the Fortin modded TS808 (another board offered @ pedalpcb)
you'll notice this also employs red clipping diodes:

(side note - i also use overdrives to boost/tighten high gain amps e.g. Peavey 6534+ and incidentally tune to drop C as well)

another good circuit to check out would be the Maxon OD808X (i've played a friend's OD808X into a 6505+ and it's awesome)
 
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@owlexifry What about doubling up on the 4148s for higher headroom, tried that?

ie instead of a single set of diodes:



...double up the foreward voltage for more headroom with close (if not) the same sound:
→→
←←
 
@owlexifry What about doubling up on the 4148s for higher headroom, tried that?

ie instead of a single set of diodes:



...double up the foreward voltage for more headroom with close (if not) the same sound:
→→
←←
yep, i actually prefer this to LEDs for more forward voltage/higher headroom.
i haven’t tried tripling, but maybe i should 😏
 
Here’s an idea for a mod - the OG circuit has a noise gate, probably THAT based, that the PPCB board omitted.

What about adding the JSX noise gate somewhere in the circuit? It’s small enough (a pot and two diodes) that it’d be easy to add with minimal modding to the board (you’d probably need to cut one trace), and it’s not the greatest noise gate ever but it seems to work well enough for AmpTweaker.
 
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