3/3/22 Update: I made a few mods to my Paragon build and so far I'm really digging it.
I swapped out the jacks to Switchcraft TS jacks for a little more wiggle room and also put the I/O and DC connections on pin headers with plugs.
This makes it a lot easier to pull it all apart and tinker with it. I'm probably going to be using this pedal for some more experiments before landing on a final configuration and build a more "proper" pedal. Funny that it went back together a bit more catty-wampus than it originally was. My initial hole drilling for the enclosure was a bit lacking in precision
Mod 1: As per
@Chuck D. Bones suggestion, I swapped out the B100k Gain pots for B250k Pots.
I actually killed channel two when I first did this and took me a while to troubleshoot and figure out what was wrong, turned out to be a bad 250k pot I installed, duh....probably should have checked that first
But, in 25 years of modding guitars and stuff, I've never had a bad potentiometer....ever. Weird.
There's definitely a wider gain range now in the sweep and more gain on tap. Just anecdotally it feels like about 1/4 rotation more gain than before with the 100k pots. Yet at the lower end of the range it can still sound like the classic KOT "pushed clean" sound. This really seems like the "best of both worlds" option rather than swapping R3 and R7 or putting them on switches. (Or ordering the "High Gain version KOT"
In the "distortion" hard clip mode there's definitely a lot of gain available. But there's also the attendant volume drop of that circuit. I'm thinking about possibly taking out the 1S1588's and socketing those pads and trying some different diodes. One thing I'd like to try is running a pair of BAT41's in series in place of the 1S1588's and see if that helps with the volume drop.
Mod 2: I came across a really cool post by
@ckaudioeffects "
Paragon PCB Mods" with a most excellent tutorial and schematic included. Some of the things he addressed were what I also thought could be improvements to the Paragon build and bring it a bit closer to the KOT. The stock Paragon build sounds a bit bright to me and a little "thin". Seems to be missing some of that "magic mid-range" effect of the original KOT. I decided to try his "Warmer Tone Mod" by swapping out a few key capacitor values. (C1, C4, C12, & C15). Of course I did not have a 33nf film cap on hand so the red ones you see are cheap Amazon ones that I was able get next day delivery. Ugh, tolerance levels were all over the map but I picked out the 2 caps closest to 33nf for those swaps. I have some WIMA's coming in my next Mouser order. The other thing
@ckaudioeffects suggested was to piggyback a 56pf MLCC in parallel to the 220k resistors at R7 and R21. Of course I did not have a 56pf MLCC cap (hahah) so I used 68pf. I may go back and change that, but the idea is to filter out some of harsher high end "fizziness". I'm really happy with how this has "warmed up" the pedal.
I don't have a real KOT to compare to but in some side by side comparisons with my KOT clone (DemonFx "King of Drive") the Paragon is much closer sounding than it originally was in stock configuration. Overall it's got a bit more mid-range warmth, there's more perceived output volume than originally. The DemonFx pedal has an internal HiGain switch which swaps the resistor value. Comparing the two at the high end of the gain range the Paragon with the B250k pot mod has a tad more gain but the MOST important thing is that with the 250k pot there's more gain "range". There's gain available in a lot more of the sweep especially towards the lower end. That's not the case with the "fixed resistor value" high gain option. So THANK YOU
@Chuck D. Bones, what a great mod! I can get everything from a cranked plexi on one end to a lightly pushed Mark Knopfler/John Mayer on the other end of the sweep. The biggest difference I'm hearing between the two pedals at this point is the 18v vs 9v headroom. The Paragon has a bit more headroom which slightly changes the upper mid-range of how the gain sounds. Also, at 9v there's a different "feel" under the fingers so to speak.
I'm still mulling a few other more mods I'd like to do,
1) Is to get the clipping switches exposed and onto mini toggles. I'm thinking ideally to use 2x DPDT On-On-On mini toggles (like on the Prince of Tone pedal) with Boost, Overdrive, Distortion options for each side.
2) I'm still debating whether to completely eliminate the charge pump circuit or make it "selectable" as per
@ckaudioeffects.
I actually have everything I need to build a Paragon Mini, which doesn't have the charge pump. So I may build that first and see how I like it.
Also since building this Paragon I've also built a Bluesbreaker clone (The AionFX version). I really don't care for how that pedal sounds with the stock 1N914's and I've been messing around with some different diodes and IC's basically trying to "KOT-ize" it
So depending on how those experiments go, will inform where this Paragon goes next with the mods. But as it is, it's really an extremely versatile overdrive and I'm starting to "get" why it's so popular.
On deck, I also have a Klon clone ready to be built (AionFX "Refractor) with a bunch of different diode options to try. As well as a couple of boost pedals ready to be built (PedalPCB's "Cleaver" and "FDIC" and a GuitarPCB "Stage 3 Boost/Buffer"). Oh and a PedalPCB "Derailer" that I'm waiting for one more order of parts to come in for
This has really become an "unintended hobby". Definitely the last thing I was looking for was another obsession in my life haha. But I'm also having a blast. Thanks to this forum I'm getting a crash course in pedal building!
M-