9B-ST for Home Theater Amp


I am using an Acurus 125x5 for the home theater surround setup, but I think my speakers need something with more bass control. The "slam" that I like is just not there in the mid-bass and lower frequencies. Can I get that out of a Bryston 9B-ST? I have the 4B-ST for my separate audio system, and the thing rocks. I'm worried that with a 9B I'm basically just buying 5 3Bs. Anyone have any other recommendations aside from Bryston? I thought about waiting around for the new 6B-ST and combining it with a 4B-ST, but then of course I'd have to get a new amp for my audio system. Ahh, decisions, decisions. Input would be appreciated.
argent
I am currently running a Bryston 4B-ST for my front speakers (Vandersteen 3A Signatures), and a 5B-ST for the center channel and rear surrounds (Vandersteen VCC-1 center, and Coincident Triumph Signatures rears), and my system definitely has all the "slam", dynamics, and power that I need. Since you already own the 4B-ST, and want to ensure that your system has the power you want, I'd suggest you buy the 6B-ST. I have already talked to the dealer where I bought my 4B-ST, and he will sell the 6B-ST for around $2800 (versus $3800 MSRP). If you want to contact my dealer, drop me a private E-mail and I will give you the contact information.
Thanks for the responses. I auditioned Aragon (Palladium, 8008) and Proceed when I was looking for my audio amp. I settled on the 4B-ST. My impressions were as follows:

Aragon - musical
Proceed - raunchy power
B&K - had punch, sort of
Bryston - pure control

The Bryston literally tamed the bass drivers into submission. And that's really what I'm looking for. Thanks for the info, Sdcampell, on the 6B-ST, but I have a pretty good relationship with my dealer. I know he'll cut me a good price. I have thought about going with the 5B for the center and rears like you mentioned. Possibly an 8B to bump up the power for the center channel. Have you noticed any sound drop-off or sluggishness in your center or rears because of the power varience between the 4B and the 5B? That is my main reason for waiting on the 6B.
Argent: I have found the 5B-ST to do an excellent job handling the center and rear speakers. I need to qualify that statement, however, by telling you: 1) the Coincident rear speakers are 3-4 db more efficient than the other speakers, which means the effective power (at the speaker) is almost identical for both amps. (Bear in mind that each 3db increase in speaker efficiency reduces by half the amount of amplifier power needed.) 2) My listening room is not very large, so my speaker setup is essentially a "near field" listening environment. 3) I do not tend to listen at "wake up the neighborhood" levels (although I have a subwoofer, and the Vandy 3A Sig's go down to about 26-28 Hz). All of that said, the center speaker and rear speakers generally do not require as much power as the front speakers, assuming your main front speakers are full-range. Most rear surrounds do not go much below 65-70 hz, so the amp does not have to drive a lot of bass information. I would summarize by saying that unless you have really inefficient center/rear speakers, have a large listening room, and/or like to listen at ear-bleed volume levels, the 5B-ST will probably do an excellent job for you. At the very least, ask your dealer if you can borrow a 5B-ST for a weekend home demo. I think you will find the 5B-ST to be very satisfactory. I bought mine for $1800 new, with full warranty. I have also thought about selling the 5B-ST to buy the 6B-ST, but the 5B-ST provides ALL the power I need for surround sound, so it makes little sense to spend another $1000 or so to buy more amplifier than I need.
I use Energy C-8's for front, C-6's for rears. Energy has no comperable center channel, so I went with the most neutral speaker, PMC LB-1 (essentially a professional monitor). I know I've broken every rule in the book by using a different tweeter and driver cone than the rest of my system for the center channel, but I must say the PMC does not color the sound at all. The transition across the front three speakers is seemless. But the PMC just strains the heck out of the center amp (Acurus 125x5). The Energy's are extremely efficient, but need to be tamed on the lower end (enter by Bryston 4B-ST). The PMC is woefully inefficient, but it utilizes a spectacular Dynaudio driver. This is why I toyed with getting an 8B and splitting it into a three channel amp (mongo power for center, and 120 at the rears). I feel that 120 on the center may be a hair underpowered. But if an 8B is more expensive than a 6B, I may just get the 6B. Anyway, thanks for everyone's assistance.
One final thought, Argent. While Bryston rates the 5B-ST at 120 wpc, their ratings are conservative. If you look at the laboratory test spec sheet that came with your 4B-ST, you will find that your amp actually produces in the 290-300 wpc range. Likewise with the 5B-ST: it produces around 150 wpc. Bryston amps have a lot of "slam" and bass control because they have very large power supplies, with top-quality toroidal transformers. Unlike some manufacturers that rely on 2-4 very large capacitor "cans" to filter the power supply, Bryston uses a number of smaller caps located very close to the output transistors (similar to the "distributed node arrangement" -- DNA -- used by McCormack in the "DNA" line of amps). The power supply, which doesn't have a "power" rating as such, has a great deal to do with an amp's sound quality, control, dynamics, transient response, etc. Hence, when you consider "smaller" Bryston amps, bear in mind that their actual performance is going to be better than its "statistics" may suggest.