Hi there,
a few things you could do would be to set MIDI clock out on one of the factors and sync the midi clock on the other units, so when you set the tempo on the first factor…. The others would sync.
another option is to set ALL the factors to Sync to MIDI clock and the take a feed from your drummers metronome?
you can set a midi cc to tap tempo too, although the midi sync would probably be easier and less prone to errors IMHO
