The “3” does three isolated tracks plus a two channel stereo down mix.
The “6” does six isolated tracks plus a two channel stereo down mix.
The “3” can do five channel input and two channel out over usb.
Where the “6” can manage eight in and four out.
I'm also interested in understanding this thing. I.e. mixpre 6 has 4 xlr inputs + a stereo 3,5 for an additional stereo microphone. But, the device has only 4 preamp, so this are the questions:
1) Must the 3,5 input be intended as a pure line-input, with no preamp stage, no gain etc? In that case I guess you could just plug a line signal - i.e. a line out signal from an external preamp or mixer and provide the needed gain before. In case this is correct, I guess that mixpre 3 could allow to record simultaneously with 5 mics and mixpre 6 with five mics ( providing the extra two mics with their own powering and gain)
2) Does the 3.5 input provide gain? In the specs the Aux-in is described as having a line or mic mode with the indication of 30 db of gain. That would mean there is another dedicated preamp stage in addition to the 3 or 4 Kashmir preamps, which I don't think is advertised, though
So the main question is how many microphones can be actually used at the same time with these devices?
Thanks all