For a while, I've been meaning to do a Centaur-based circuit. I have built quite a few of them in the past including an Aion Electronics Refractor as well as a few Ceriatone Centuras. Since then, there have been quite a few sources popping up on eBay, AliExpress, Alibaba, etc. for inexpensive enclosures and some include 24mm pots like these:

• https://www.ebay.com/itm/192877786625

• https://www.ebay.com/itm/333696285006

My goal with creating a new circuit board was:

• 1:1 Signal of the original Centaur

• Thicker signal and power traces

• Similar layout to the original and compatible with real Centaur enclosures (or clones such as eBay/Ceriatone Centura enclosures)

• Eliminate jumpers

• Utilizes the 24mm Alpha PCB pots from the eBay kits

• Make the circuit board BLACK

• Improve the grounding and overall manufacturing utilizing 2-layer 1.6mm boards.

I really am happy with the results! I have built two so far with the v1 circuit boards and they sound fantastic! Rather than copying the components 1:1, I carefully selected high quality alternatives to the original parts selection. Assuming you've bought the kits from the above two eBay links that includes the pots, you can toss away their circuit board and use mine :-)

Build Resources:

Circuit boards can be purchased here

Note: V1 circuit boards will need a jumper (I already installed this if you ordered a PCB) across pins 1 & 8 on the 18v charge pump IC so the clock frequency is boosted to ~35kHz.

Two BOMs here assume you've bought the eBay enclosures that include the 24mm pots. For "magic diodes" are germanium-based with a forward voltage drop (vF) of .35v. Buy a few of them so you can measure using your DMM.

https://www.pedalhackerelectronics.com/category-s/1852.htm

https://smallbear-electronics.mybigcommerce.com/germanium-signal-1/

https://stompboxparts.com/germanium/

I recently bought a bunch of these with good luck finding exactly .35v

Traditional Centaur Component Selection.

https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=1c049146b1

The early Centaur (up to mid-silver enclosure) circuits used bi-polar capacitors for C9, C10, C2, and C15. These are green MUSE caps in the BOM.

The later Centaur and new Centaurs use standard electrolytic capacitors for C9, C10, C2, and C15. You can follow the very nice Ceriatone Centura Documentation for circuit differences since the layout is the same.

The Tone Geek Touch Component Selection

https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=982f1603f6

I'm still tweaking what this perfect component selection looks like however every option I'm considering is included int he above BOM.

Build Video Coming Soon!

For those wondering about the BFK designation, it's a throwback to my favorite 1990's video games Doom and Quake. This time it's Big F*cking Klon indicating that it's for the full size enclosure. I have a 125B already made that I need to test so stay tuned!