I'm going to be using a passive diy sub powered by an external amp with my 2 channel system. My preamp has dual outputs, the XLR's are going to my main amp and so there are a pair of RCA's I can use to run the sub. (this is how I was running the system with my Infinity IL120s which has a built in line-level crossover). So I am looking to get an external low-pass crossover to use the new DIY sub with the full-range outputs of my pre-amp. The sub was very affordable so I really can't justify spending more than $100 on a XO, and if I can get it done for much less that would be great. (this rules out Marchand stuff) Are there any comparably priced XO's that compete with the Paradigm X-30? With my particular application I don't need the high-pass outputs at all (because I just feed the mains with the other full-range signal from the pre-amp) so it seems like a waste to buy the X-30, but I keep hearing that products such as Harrison Labs FMOD, which seem like they would be perfect for the application, are not up to the standards of a high fidelity two channel system. so what's the cheapest solution with the least compromise? Also, if I do use something like the FMOD, can I sum the L&R outputs simply with a reversed Y-splitter, then insert the FMOD, then use another Y-splitter to split the signal and feed two amplifier channels (it's a two driver sub)?