I am looking for a two way RCA input/output crossover. It would be nice to have the xover be adjustable, but if not it should be around 80hz (or a little lower). I was looking at the Rolls SX45 and that looks like it would do the trick, but I read a couple reviews on amazon and apparently the build quality sucks and the high pass and low pass outputs are in opposite phase of each other. I really only need the high pass part of it (which will be used on my Paradigm Shift a2 powered speakers) because I'll be able to use the LPF on the sub (which I don't have yet). But I was thinking that it might be a good idea to run both the speakers and the sub through the xover just to make sure the phases are correct. If the sub I chose had a crossover built-in that would be ideal, but I'm not seeing many that have that. I was looking at the KRK10s ($399) which has pass-through, but the 12" version (for $799) has a crossover. I was looking to spend around $100 (or a little more if it really makes a difference) on a crossover. I've seen quite a few that use XLR ins and outs, but not many that use RCA. I hope I made it clear enough about what I'm looking for, and I hope someone will be able to point me in the right direction with a few suggestions!