i just have jammed some hours w/ a macbook pro (ableton live 8.0.4), apc40, motu ultralite and pioneer djm-600.
used 8 outs from the motu into 4 stereo channels.
i wanted to give a try to a 4 channel stereo mixer configuration, thinking about buying later the denon dn-x1700.
my ableton session is based on 8 columns (tracks).
so after trying and trying this is the setup which worked better for me:
djm-600 on the left, ableton apc40 on the right, macbook pro centered-right on a stanton uberstand.
i divided the session in two logical 4-parts sides.
tracks 1 and 5 are assigned to channel 1 in the mixer, and will bring effects clips (transitions, fx, vocals samples) PLUS the returns of 4 effects (A, B, C, D).
tracks 2 and 6 assigned to mixer channel 2
tracks 3 and 7 assigned to mixer channel 3
tracks 4 and 8 assigned to mixer channel 4
those tracks are the tracks with my standard tunes.
i put one auto-filter basic fx in insert on EACH ableton track, which will be controlled by the device control section at the low right of the apc40.
i selected 4 nice FXs and inserted them into 4 aux tracks (A B C D), which will be controlled by the track control section at the top right of the apc40 (i remapped PAN with send D).
so basically i'm using only the basic knobs and buttons on the apc40, but with very straightforward functions and almost no possibility to make mistakes. piece of cake for dummies (like me)!
and yes, it is a DREAM come true!!
easy and straightforward.
especially playing with the send knobs with the right hand, while controlling the returns on the mixer with my left hand on mixer channel 1, very functional and fun!
no way you can mix like that with a "standard 2 decks + mixer" setup.
i have some issues w/audio quality though.
mp3s suck.

i believe i should convert all of my library in wav and rewarp the material.
anybody did that?
how do you convert from mp3 to wav?
also, on a gain level issue, i think the best thing will be to raise all of the apc40 faders to max volume, and, clip by clip, adjust the gain so that it won't overload. no clicks and pops.
doing so, the signal which is going to the mixer will be totally clean.
ALSO, when mixing many clips together plus summing the returns, there's a risk to overload the master.
i guess i need some practice.
maybe a limiter could help?
hints?
i feel pretty comfortable with this 4 mixer channels setup.
with that denon dn-x1700 i should basically carry only 3 pieces of gear, almost no cables, and cool FX both from ableton live than from the mixer itself.
lots of fun.
anybody tried/listened to the audio quality (as pure soundcard) of the dn-x1700?
ALSO: i need a good case now. any hints?
thanks much for your comments, very appreciated.
bless from the caribbean