I'm willing to add a good quality sub x-over to lighten up the load on my amp. Supposedly, crossing over at 100hz will effectively quadruple the amps output if it doesn't have to reproduce loud bass-IT WORKS. My system: Denon cd to classe 30 pre-amp to a Janis 1/a sub amp and crossover to my Dynaco St-80 (new version 25 watt triode) to my coincident speakers. The Janis runs to a pair of nelson-reed passive subs. I didn't really need the extra power but by doing it this way, the headroom of my amp is limitless (at least it feels that way) and the bass can't be matched by most speakers.
A friend of mine did similar with an 18" velodyne sub between his pre amp, EAR monoblocks and Quad esl63s. Not only did it bring out a lot of bass, it cleaned up the rest of the frequency since the power hungry quads didn't need that much any more.
A friend of mine did similar with an 18" velodyne sub between his pre amp, EAR monoblocks and Quad esl63s. Not only did it bring out a lot of bass, it cleaned up the rest of the frequency since the power hungry quads didn't need that much any more.