Axiom Home Page Forums General Discussion Technical Questions Sub Out vs. Line Level

I have never seen a real comparison between the two inputs but I would expect that the line-level "sub out" signal would be higher quality since it doesn't have to go through the power amplifier.

If you had a tube amp with a transformer-coupled output it's possible that using speaker outputs for the sub would help with ground loop problems (since the transformer output can float relative to ground) but AFAIK all modern solid-state amps use ground for one of the speaker outputs.

That last point is not true when the amplifier is bridged but I don't *think* a bridged amp would help since both of the outputs are still "relative to ground". Not sure though...

I assume you tried all the normal things like "remove that little screw Axiom included to float something in the amplifier" ? Ground loops on the EPxxx subs often seem to be related to the cable TV and/or satellite TV inputs to the receiver -- it's worth disconnecting them if only to find out which one (if any) is the culprit so you can eventually yell at the cable/satellite vendor enough to get the root cause fixed. Until then, those Jensen transformer widgets do seem to really help...