He would go TT’s to his soundcard input and the outputs would go to the controllers inputs. You’d treat it as regular external inputs. So none of the buttons on the controller would be operational. Essentially you’d be using it as just any other mixer.
There is no way to have two laptops attached to one controller (with the exception of the Pioneer DDJ-SZ/RZ and the new Denon MCX7000.
So you’d have two laptops side by side. One with Traktor to do DVS (again, without any extra features) and one with Serato that would have all the controller functions operational. If you set the inputs from the DVS sound card to channels 3 and 4, you can use all 4 channels simultaneously (2x DVS over Traktor, 2x regular Serato decks) and have the sampler.
The SX2 has no built-in FX, so even those are not there for DVS, with the exception of the filters.
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