You are trying to get that magical thing in audio, quality for (nearly) free 🙂
The Audio Kontrol 1 is primarily aimed at (home) producers, it has a mic input/preamp and such and the outputs (4 for 2 stereo channels) are Jack, which is rather unpractical. The sound quality is high. I think it’s a 24-bit/192KHz sound card.
More importantly though, is the way you want to hook things up. If you want to keep using the headphones through the controller, you would only need a 2-channel (1 stereo) USB soundcard. The one that gives you output to your speakers. This will only work if you can set things up properly in your DJ software.
If you were to use the Audio 2, which is more geared towards DJ purposes and doesn’t have the quality sound card of the Kontrol 1 but should sound fine for the purpose (CD quality track playback), you could hook up both speakers and headphone to it, with less setup problems.
As for Linux drivers … well …
Hope that helps some.
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