The Black BBD has two BBD lines that work together for smoothly fading multi-tap delays. It has its own LFO and some advanced clock noise cancellation circuitry.
It’s a classic, grungy sound and the Black BBD has it in spades. It’s not content to be left alone either and the hands-on controls like to be fiddled with whether by fingers or control voltage.
The two BBD delay lines work together and are blended by a crossover knob taking you smoothly from a short 1024 stage to a longer 4096 stage. Time is controlled via the large knob at the top and can push things further than you’d imagine particularly when you add some CV. At long delay times you’ll get some high-frequency artefacts creeping in due to the sample rate reduction. Time is also pushed about by the internal LFO. It can be a square or triangle waveshape or something inbetween.
The advanced BBD noise cancellation circuit reduces the unwanted BBD clock noise but without taking out all the high frequencies. However, you can dull things down with the Colour knob that introduces an extra lowpass filter.
The Feedback knob can push the module into self-oscillation when used in combination with the delay time for an interesting bit of droning.
For outputs you have a mix output that’s controlled by the wet/dry mix knob and an additional Wet output for taking the processed signal out to other places. CV control on Time, Feedback and Mix add to the modulation possibilities.
It looks like Erica Synths have squeezed as much possibility out of the old BBD delay circuit as they could find. The sound demo takes it into all sorts of places I wouldn’t have imagined.