Originally Posted by Wolfgheist
What rules apply with subwoofer coaxial rca cables?
That is a completely different subject. But if you search Google you will get links to speculation on the common limit to RCA Coaxial Cable.
Relative to the RCA cables themselves, is the resistance of the internal wire and the degree of shielding. Many of the ultra-thin ultra-cheap RCA cable would be luck to have 10% shield coverage. Many of the better RCA wire has about 95% coverage. Many decent acceptable cables have about 55% shield coverage.
The less coverage the more likely they are to pick up external noise.
I've seen 15m (50ft) mentioned and I've seen 5m (16ft) mentioned. But since it is very cable dependent, it is hard to lock down one definitive answer.
Here is a link that say 30m (100ft) MAX, but that is making a lot of assumptions.
Perhaps a better question is - How far do you need to go?
As the cable gets longer the signal starts to deteriorate, how much can you handle?. Typically signal deteriorate in the high end first because of cable Inductance. That's less of a problem for a Subwoofer Cable.
The mating impedance of the Sub input is relatively high, in the range of 10k ohms to perhaps 50k ohms, so you can tolerate pretty substantial Resistance in the cable before it become a significant signal loss.
To lose 1% of the signal into a common 47k ohm input, the wire resistance would have to be 470 ohms.
22 ga wire is 16.14 ohms per 1000 feet.
24ga wire is 25.67 ohm per 1000 feet.
How long does the wire have to be?
What quality of wire are you buying?
I would say, though extremely variable, you could probably tolerate up to 50 feet for a Subwoofer. I would be more inclined to say about 20 feet for a full range cable, but that is just an intuitive guess.