Neither the A4 or Analog Keys will “midi sequence” anything, with CV indeed their only external sequencing on their own abilities. The Analog Keys will only act as a midi controller at push of button while you still could have the AK sequencer running, but not driving anything via midi by sequencer.
There’s the original Waldorf Pulse Plus (only the ‘PLUS’ version) that has not only extensive midi implementation, but also extensive CV INS/OUTS, and also will work both ways as a CV to MIDI/MIDI to CV converter. Not sure if the expensive Kenton Box would do what you want with the Volca Bass or if the Volca is able to be circuit-bent like the Monotribe can be.
Really hoping with OverBridge, the ability for A4/AK to midi sequence at least bare minimum note data.
Thanks for the reply. Shame it won’t sequence external MIDI, I’ve read a few posts bemoaning it.
Ironically, I sold my Waldorf Pulse (though not the plus version) to help fund the AK purchase! I loved that little beast. I’ve just read that the Monotribe has an update which allows for CV input, though I think it’s only gate. There’s even a video of someone CVing one with an A4.
I actually really like the Volca and would prefer to use that (also, the Monotibe is borrowed!) I can borrow one of those Kenton boxes, so I’ll give it a go. Reverse MIDI to CV… never thought I’d be trying to do that!
I don’t quite get the ‘midi controller’ switch, though I’m sure it will make sense when I finally get my order. I take it midi clock is transmitted the whole time, whether the switch is enabled or not? At least that way I’ll have the Volca in time with it’s own sequencer.
Found that on the A4 subforum posted by coreyappleby
Basically rerouting the CV back into the AK/A4 and pushing up the LFOs to audible range. I’ve gotten tons of sounds using this and kind of wish I had read this before buying a microbrute (although microbrute is a lot of fun 
)