Amp-->cable-->XLR multicore-->Cab ??

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http://pro-audio.musiciansfriend.com/product/Radial-SGI-TXRX-Studio-Guitar-Interface?sku=153923
 
Much better to have a really long speaker cable, keep the head in the control room, and the cab in another room though! Unless you're recording a combo...
 
Yeah dude, just make one, soldering doesn't get much easier than speaker cable to jumbo 1/4" plugs! :D