There seems to be an opinion (can't remember where I read it, sorry)that the new models (14B and 6B) have addressed some of the issues surrounding the lack of midrange niceties that the 7B and 4B amps are perceived to lack. I own a 4B-ST and can't find anything wrong with it but I haven't tried either of the new ones to see if there truely is any difference. I think it comes down to what are your main listening pleasures - 2 channel, 5 channel DTS and the like or HT(movies). If you are going to use the 3 channel amp primarily for HT then I very much doubt any sonic benefits that may be in the 6B over a 4B will be realized - HT wiz bang and the like... But hey thats just my opinion. If its just a center channel issue, what about a Powrerpac 250 (one side of a 4B)- retains the timbre/amplification of qualities of the 4B...
Tough call to make - I guess I haven't really answered your question...
Tough call to make - I guess I haven't really answered your question...