An All New Thagomizer... Almost Literally... (AionFX Nucleus)

Fingolfen

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Unless you've been under a rock, you know I really like the Colorsound Power Boost circuit, especially clones that use vintage components. Unfortunately, there are a finite number of vintage components available in the world at this point, and eventually supplies will run out. Vintage components are also more expensive than their modern counterparts, so I wanted to build a Power Boost clone on the AionFX Nucleus board with new components to see what impact it made on the tone of the pedal.

Aion Nucleus - Thagomizer Mod - 01.jpg

As you can see from the board above, all of the resistors are modern 1% Yageo metal film. The capacitors are modern WIMA, KEMET, and Nichicon (electroyitc). The diodes are all new as is the integrated circuit (though the IC is new on all of my builds as it is part of the 18V charge pump). However, I did cheat a little and the transistors are still the BC169 and BC184 combination I've used on all of my Thagomizers since the very first build.

Aion Nucleus - Thagomizer Mod - 02.jpg

As for the rest of the build and internals, it's pretty much exactly like all of the other Thagomizer builds I've done. I'm using a star ground on the input jack. All of the jack connections are heat shrink wrapped. These also include a battery snap as there is room for one in the enclosure.

Aion Nucleus - Thagomizer Mod - 03.jpg

The enclosure itself is in the same theme as the various Thagomizer I vintage pedals, but as this one has all "modern" components, I went with different art, fonts, and a different color. Tayda has recently released several new metallic colors, so I used this opportunity to try one out. This one is the metallic dark gold version, and I really like how it looks. I'm going to have to find ways to use it more going forward.

Aion Nucleus - Thagomizer Mod - 04.jpg

In terms of sound, it sounds very similar to the vintage ones, but not identical. If anything, I'd say it has a slightly "brighter" tone - at least with my Chapman fed into my Boss Katana amplifier. I'll likely end up using this one as a "travel" pedal for lessons, etc., while the vintage one will stay at home unless there's a major performance in the works.

Also at the blog: https://steggostudios.blogspot.com/2022/09/an-all-new-thagomizer-almost-literally.html
 
Looks great! I too am a Colorsound Power Boost enthusiast. I built the Aion Plasma (new, 9v version) a while ago. Later I built the Nucleus (18v version, on-board charge pump). Both were very "utilitarian" builds, plain enclosure, label maker labels. They worked great, but I wanted something nicer looking, so I built the Madbean MeatQlaw.

Now I'm working on my own Power Boost PCB. It's basically a clone of the Aion Nucleus, but also incorporates a relay bypass circuit on the PCB. The result is less off-board wiring, and much shorter input/output cables in a 125B enclosure (i.e. don't have to route signal wire from top down to the footswitch, to effect PCB, back to footswitch, and back to top of case).

I built up v1.0 of my PCB last weekend, gut shot below. I had a number of problems: all my controls were the mirror opposite of what I intended (per my MeatQlaw writeup, I originally did the waterslide decal on a 125B, before I realized the MeatQlaw is intended for a 1590B)! So in order to not waste that 125B enclosure, I made my PCB have the same potentiometer locations as the MeatQlaw. I got the orientation exactly right, just flip-flopped bass-treble and gain-volume! I also forgot to add a current limiting resistor for the LED. I made the footprint for the relay backwards (in the pic below, the relay is on the other side of the PCB, the intent was to have it on top). It took some time to sort all that out, but a corrected version is in the works.

Anyway - how do you use your Power Boosts? I've gone back and forth on this circuit, but something always pulls me back to it. Maybe it's the "uber mojo" of being one of the very earliest overdrive/boost circuits? It's quite versatile, and I haven't really encountered anything quite like it. I sometimes use it for a a little light overdrive - it's hard to dial this in nicely at bedroom volumes, though. I'm sure you've by now heard the "splatty decay". That sound is very prominent at bedroom volumes, but is mostly drown out at band volumes. I also use it with my Dynamic Haircut (Barber Gain Changer clone), it seems to mate pretty well with that: I can use the Barber for a bit of grit (that sounds good at both bedroom and band volumes), and then kick on the Power Boost to push the GC harder. And still other times, I crank the gain pretty high and play with the fuzz its capable of.

Kit Rae has a lot of info on the Colorsound Power Boost and Overdriver, if you haven't seen that already. And of course, That Pedal Show: Colorsound Power Boost-Style Pedals is a fun watch.

Since you're using a Katana - do you ever use the headphone out of this amp? I'm curious how your Power Boost (or any of your other pedals for that matter) sound through the Katana's headphones.
 

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I'll check those out, though honestly my next Colorsound build is likely to be even more old school (ooohhhhh... foreshadowing)...

I haven't used the headphone out on my amp, though I should... I'll give it a try and let you know...
 
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