I would just convert everything to xlr I/o and get studio subs or if you know how to convert a sub by removing the speaker inputs and attenuator and installing the XLR i/o on the subs that would be another option.
I wouldn't run RCA interconnects because of the potential ground loops that might happen.
I wouldn't run RCA interconnects because of the potential ground loops that might happen.
If you want to keep RCA then I would still wire it as XLR and get XLR to RCA transformer adapters . This way, you can run a long run, with little loss and it would never ground loop. Also, this will future proof the install with modern hi-fi standards and open up options in the future for replacements because you will not be stuck with an RCA run that isn't going to do well past 20Ft. and my cause ground loops.. RCA interconnects were never designed to be longer than a 6 foot patch originally.
Well, either way- i have run shielded two-wire cabling in the walls, and will have options to do things different if needed. I'm sure that it will do just fine for subwoofer duty.
If needed I can experiment with grounding the shield at either end to find the best noise performance.
If needed I can experiment with grounding the shield at either end to find the best noise performance.
I'm a stadium installer and not a home theater installer. For your application of subs, the little pro stage transformer box adapters work just fine. I use a special one with a 3.5mm jack to get laptops into the 68KW stadium system I run for a living noise free. These boxes run you somewhere $35 to $75
For my rack to rack long runs I use Jensen DIN series transformers and mount them on a din rail in the back of the rack. They are about $120/channel, but they are the best sounding ones I have worked with and the best bandwidth performance (2hz to 200 Khz on most models)