Just want to add my particular experience in contrast to Cornfedboy. I owned the Sixes with battery supply, before I did extensive auditioning of the 112, the 10 and ultimately bought the 12's. My experience on my Vandy Fives was that I preferred all three of the latter to the Model 6's. The 6's seemed to lack the resolving power and punch of the other three.
Also, I do think there is something to what Brulee says. I've never heard the Spectral, but I did feel that the Sevens never had the punch that amps of that size should have. I actually had four monoblock Sevens powering Soundlab A-1s and B-1 bass panels. That was an interesting combo, but it never did seem to be quite right. It wasn't until the B-1 panels were returned to the factory that Roger West discovered one of the bass panels was wired out of phase. I won't embarrass any of the several high end luminaries who heard my system and didn't catch that problem through listening.
In any event, the Sevens did quite well on the A-1s, but I remember they had real trouble driving a pair of Apogees (don't remember which model).
