compactrobot wrote:First, can the MOD rate sync directly to the MIDI clock, or is it only synced to the ARP/SEQ, which in turn is synced to MIDI?
The LFOs always sync to whatever clock source the ARP/SEQ is using (which is the "master clock source" for the Sub 37)... you can have the Arp OFF, of course, but if you want the LFOs to sync to incoming MIDI you still need to have the SYNC button turned on in the Arpeggiator section.
compactrobot wrote:Is there any current method for automatically modulating the filter cutoff in sync with and over the duration of a programmed sequence? In other words, I'd like to have MOD 1 modulating he filter cutoff, with the rate of MOD 1 in sync with the start/end points of the sequence, such that the filter sweeps once per sequence loop.
You should be able to accomplish this by using an LFO with SYNC turned on, and setting the LFO clock div to the same number of beats/bars as your sequence (1, 2, 4 bars maybe). Additionally, you can go to PRESET EDIT -> ARPEGGIATOR and set STEP 1 RESET: ON... then turn on KB RESET for the LFO. This will force the LFO to restart on beat 1 of your sequence. If your LFO Sync clock div is the same number of beats/bars as your sequence, then you don't necessarily need to also do the KB Reset, but if you do, it will ensure that the phase of the LFO is always the same relative to your sequence as well.