jim's adwice is good. (i know - he also likes alfas!) i use two adcom gfa555's to drive my 4 ohm vmps larger subs. i was running 'em bridged yust fine, but due to all the recent talk of bridging halving the load the amp sees, & halving the current it outputs, i tried using yust one channel of each amp in stereo-mode. well, the bass *is* yust a mite tighter. w/the subs being 95db/1w/1m, 325wpc is adequate! :>)
re: x-overs i use the marchand xm-9, & it *is* an excelent unit - wery transparent, & *wery* flexible. while i haven't a-b'd it w/a well-known & respected unit such as the bryston 10b, more than one person familiar w/both units has told me the marchand is more transparent. at half the price of the bryston, this is a good ting! :>)
doug s.