6hp left?
Doepfer A-185-2v Precision Adder.
You can then have one sequencer transpose the other, in tune, up or down,
and then share those new notes to that nice top row.
The power supply is fine.
The modular ribbon cable never carries audio. Just power and ground,
and sometimes, one gate for event on/off, and one cv, usually for notes.
Those two Moog sequencers are very different animals and can play nice together,
but the Subharmonicon is a demanding instrument to tame and integrate into a mix.
It's harmonic based, and always brings it's own special notes.
Spectravox is even weirder. For me, both of them are more for seasoning than a main course.
If you like that three-tier Moog format, consider maybe two Mother32s might take you further.
That'd be fun.
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