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What Al said.....
Something like these would work if you already have RCA cables
http://www.musiciansfriend.com/accessories/live-wire-rcaf-1-4m-adapter-2-pack/330870000000000
Most pro gear these days will work either way, and like your crossover if you plug in a single ended 1/4 inch plug it will automatically configure itself for SE operation.
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What Al said.....
Something like these would work if you already have RCA cables
http://www.musiciansfriend.com/accessories/live-wire-rcaf-1-4m-adapter-2-pack/330870000000000
Most pro gear these days will work either way, and like your crossover if you plug in a single ended 1/4 inch plug it will automatically configure itself for SE operation.
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