With a shit load of poly capacitors on one of its PCBs, and looking like a snake-oil PC power filtering PCI card advertised on Ali Express, Antumbra’s BANK is a Eurorack adaptation of Yusynth’s Fixed Filter Bank, which in turn is inspired by Moog’s original 914 Filter Bank module.
Build wise it’s a mix of 0603 components, SOIC-14 (if I remember right) ICs and loads and loads of the previously mentioned through-hole poly caps. There’s a build guide on their site that I can’t really add anything to – like it suggests, taping the poly caps in place with masking tape and soldering them all at once is the best way.
It’s described as a difficult build – it’s not especially, if you’ve done any of the MI clones, etc, you can do this – there’s just a lot of it.
I’d made one small mistake on this build, overlooking soldering one side of a single component – as a result, everything was working except the 350hz filter band. I tried looking at the Yusynth schematic but couldn’t translate it in any meaningful way to the Bank PCB.
David at Antumbra was kind enough to send me the schematic for this section, which made finding the problem a lot easier. I then noticed the components for each frequency band are marked on the PCB. Doh.
PCB & panel: Pusherman