Blaknblu Foxtrot

You may have heard it said that you can never have enough VCAs, but Blaknblu would suggest you can never have enough filters. The Foxtrot quad‑multi‑mode filter has 12 of them. At 38HP, it’s very wide, but the front panel accommodates four individual and complete multi‑mode filter modules, each with a choice of three topologies. The idea is that you’ve got four independent and identical filter channels. Each filter can morph from band‑ to low‑ to high‑pass. You have two mono inputs, dual or stereo outputs, two CV inputs for the cutoff and an assignable ‘Aux CV’ that can control the filter mode morphing, resonance or panning. Lastly, there is a Boost switch for a little bit of overdrive. Behind the scenes is some clever routing to link the filters into a parallel bank controlled by a single cutoff, if you so wish.

Each filter can be one of three types. First, we have the friendly bounce of the Moog‑style ladder filter, followed by the unruly nature of a Sallen‑Key (SK) filter from the likes of the Korg MS20 and, finally, a buttery state‑variable (SV) filter similar to the Oberheim SEM filter. The Boost switch is tailored to the specific...