Originally Posted by NEO Dan
After re-aranging my system I accidentaly hooked up a known to be good subwoofer with a spare "high end" cable, and I was shocked at how crappy it sounded. As it turns out it was a silver plated sissy cable for my DAC, hence the 75 ohm impedance and it sounded like $hit as a subwoofer cable.
OK. I run RG-6U cable capped off with 75ohm connectors all day long for subs and it "sounds" great, plus it's a lot easier to get than whatever magical cable/connector is the current 'fad' style (gold, braided, non-braided, twisted, silver, supercooled, golden ratio, special dielectric, special jacket, crystal tuned, non-oxygen, etc etc etc).
Thus I was just saying, that running a 75o cable isn't going to magically turn your sub into mush. If it did, then we'd have a lot of angry people all over the place who have "bad" cable hooking up all sorts of audio gear. I can't recall any demonstration that swapping 75o for 50o would make an audible difference, but swapping a 75o cable with a cracked solder joint for a 50o one with a solid connection will definately be obvious.
Even a high end silver-plated solid-gold conductor 50ohm subwoofer cable is going to sound like trash if the connector end is falling off (probably because the solder didn't stick well to the silver plate).
I'd be more worried about distortion caused by cheap amplifiers for a subwoofer application, before taking a magnifying glass to my interconnect terminations. We're talking about audio frequencies here, and the human ear is about the least precise instrument you've got. Now if you want to run microwave frequencies over a 100m run... now you've got my attention over cable impedances.
I don't care if people want to run out and buy hand-crafted unobtanium cables, but I just wouldn't want new people thinking that if their sub sounds wonky it's because they used RCA connects instead of BNC or that their cable must be silver plated or blessed by an audio priest or anything; audio is a non-demanding application. Don't forget, you're dealing with a +/- 20% tolerance also. Your perfect 50ohm cable may be 60ohm and still in spec (or 40ohm!)
For the record, all my Monoprice interconnects ("improperly" terminated at 75ohm and running RG-59U) sound great.