Hi Ben, I had to move your post from a reply to a totally unrelated post in the wrong forum to a post of it’s own in the correct forum.
Please take care to a) not ask a new question in an existing post and b) to post new questions in the right forum.
Also, there is no need to address your posts to Phil. While he may read posts here, the forums are independent of the main site. Terry_42 and I are the moderators. However you don’t have to address questions to any particular person. Just post your question and people will respond.
On-topic: Of course you should be able to hook up your mixer master out to the RCA in on your speakerset (back of the sub). Clearly this kind of speakers is made specifically for computer (gaming) use. 5.1 surround is useless for DJ-ing as you will only use stereo sound sources. If you don’t have speakers yet, you could look at low end like the M-Audio AV32 2.1 kit: http://www.bax-shop.nl/studio-monitor/m-audio-av-32-1-monitors-2-1-set.
A few steps up in quality but still good price/performance is looking at KRK (RP4, 5 or 6) to which you can add their sub.
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