amp for Bag End ELF system?

I am looking at extending my system with an ELF system (the ELF-1 crossover and bass booster and two S10E-I's). What amp, that goes down to at least 8Hz, would be good for this? I have a Musical Fidelity A3CR, but it's only rated at 10Hz, has anyone tried this?
Also looking for a pre-amp recommendations in this same system.
We are sorta in the same position. I recently ordered the elf 1 and havent taken delivery yet. I also ordered a pair of s18's versus the s10 that is to take 6 weeks or so to get with oak veneers. I am however troubled by reviews that are critical of the alleged high distortion and less than transparent high pass filter. I am trying to determine if a passive high pass filter,say 24db rolloff Linkwitz Riley, in linebefore amp might be preferable and avoid using that half of the elf. I am buying without hearing but guided by mostly favorable reviews. To answer your question I have yet to buy into the 8htz theory or the extended bandwith business. I have the sony sacd and have not yet switched to extended on the back panel. I intend on using 2 Krell kst 100's in mono(400wpc@ 4okms) to power the s18's in stereo and the Morrison ELAD with 2 outputs (1 to mains other to Elf1)as preamp, then into Krell fpb 200c.