Get a little box like this:
http://artproaudio.com/discontinued_products/product/cleanbox_pro/
At the input end run your RCA outputs from your controller into the RCA inputs on the box.
Also order two balanced XLR-TRS cables. Make sure the XLR side is FEMALE!
Run the XLR Connector from the box’s XLR balanced outputs to the balanced TRS inputs of your speakers.
Done.
Take my advice, while you could hook this up with various cables and/or adapters, I would seriously suggest against that. Spend a few bucks on the box and cables and you’ll have the best result.
For the interested: RCA is not a stereo connector. You will always (almost) see TWO RCA connectors, one carrying the left (white) and right (red) signal half of a stereo signal. XLR is also always (almost) mono.
You CAN get TRS connectors (both 1/4″ and 3.5mm) that ARE stereo, but this is either for connecting line signals to, say, a car radio (the lead that goes from the small trs jack that you plug into your smartphones headphone connector to the same small trs jack on the front of your car stereo) and on headphones. For connecting speakers, microphones and other stuff, the large TRS jacks will always be balanced mono.
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