[Grit]

Can anyone tell me if the 4B SST2 sounds at all different in any way from a 6B SST2 when playing 2 channel music? I read that all Byrston amps within a series sound the same (they just add more power). However, the 9B doesn't sound identical to the 4B at lower volume on my speakers.


I finally got to compare my new 9B SST2 to a 4B SST2. All my equipment is Bryston now. Speakers are Aerial Acoustics 7Ts (4 ohms, 89 db sensitivity).

I've done all my listening at or near the volume of a normal conversation. Nothing loud.

While they sound similar, the 9B is missing/lacking some things. It certainly doesn't play bass like the 4B. With the 9B, it sounds like I need to add a subwoofer. With the 4B, it sounds like the subwoofer is already on. Also, the 9B seems to muffle some higher end sounds. As an example, if you heard a triangle ring, the attack sounds about the same, but the trailing part doesn't decay clearly with the 9B. It sounds like someone muffled it. The 4B does it just fine.

I'm considering getting a 6B-SST2 to replace the 9B-SST2. My concern is that I can't tell if the sonic differences between the 4B and 9B are due to power, architecture, cooling capacity, etc. There are no 6B-SST2's for a home demo within 100 miles. I'd just add a 4B-SST2 and call it a day, but I'm concerned that the 9B won't provide enough power to my center channel either.

Any input would be appreciated.

[servingko]

I went through the same thing several years ago.  I found that the 6B sounded closer to the 9B than the 4B - just more power and greater dynamics, but at most listening levels they were pretty close.  This makes some sense in that the circuit layout is closer.  I also don't think the 9 or 6 received as many of the squared upgrades due to space limitations.

In the end, I am using a 4B with a 9B in my HT (5 channel) with the center passively bi-amped with 2 channels from the 9 and one left unused.  It's not a perfect match but room acoustics make the center and surrounds sound different anyway and I am using 5 identical speakers in my HT.  If you have the option to bi-amp your center you may want to try that.

I have owned every Bryston amp but the 28's and they all have a slightly different sonic signature when A/B'd with careful listening and reference material, but in the end the differences are difficult to distinguish with multichannel material, unless you are driving any of the channels into clipping.  FWIW, I have found the 4B and the 3B to sound the closest to one another, again at moderate levels as you are only talking 3db more with the 4B.  For the cost difference the 4B is a no brainer.  Having said that, I recently purchased a new 3B as the price was right and it fit in the audio cabinet in my bedroom system better.

[Grit]

I went through the same thing several years ago.  I found that the 6B sounded closer to the 9B than the 4B - just more power and greater dynamics, but at most listening levels they were pretty close.  This makes some sense in that the circuit layout is closer.  I also don't think the 9 or 6 received as many of the squared upgrades due to space limitations.

In the end, I am using a 4B with a 9B in my HT (5 channel) with the center passively bi-amped with 2 channels from the 9 and one left unused.  It's not a perfect match but room acoustics make the center and surrounds sound different anyway and I am using 5 identical speakers in my HT.  If you have the option to bi-amp your center you may want to try that.

I have owned every Bryston amp but the 28's and they all have a slightly different sonic signature when A/B'd with careful listening and reference material, but in the end the differences are difficult to distinguish with multichannel material, unless you are driving any of the channels into clipping.  FWIW, I have found the 4B and the 3B to sound the closest to one another, again at moderate levels as you are only talking 3db more with the 4B.  For the cost difference the 4B is a no brainer.  Having said that, I recently purchased a new 3B as the price was right and it fit in the audio cabinet in my bedroom system better.

Thanks for your input. I've been tentative about using the 9B for the center, mostly due to lack of bass control. However, as you said, I can bi-amp the center, and in multchannel, the low end will get routed to the subwoofer too.

I wish the 6B was an identical sound match to the 4B; that'd solve my problem nicely. It doesn't seem to be the case though.

[Rod_S]

There's always the option to get five 7B-SST2's, problem solved

[Grit]

Hahaha! If only i had the space! Unfortunately, I can only squeeze two amps in, total.

[Rod_S]

You still may want to consider the 6B if for nothing else other than more headroom and the more powerful amp's ability to sound more full at lower volume levels. This would be because it runs in class A for a few more watts than the 9 would.

As for any audible differences, like was mentioned it's possible you may hear a difference but unless you run identical speakers in all five channels the chances you would be able to discern any audible differences as the sound pans around you in the 5 channels would be minimal at best. If your speakers are different then the differences you hear are almost certainly coming from them not the amps.

I ran a 7 speaker setup for years with a 6 and two 4's, then 5 speakers with a 6 and one 4 and it was great and best of all powerful. I initially thought about the 9 to save on money and needed rack space but decided to go for the extra power and believe it was the right decision because like you I actually don't listen at excessive volume levels and feel I came out ahead with amps that can play better at lower volumes.

[Rod_S]

By the way, what are your other speakers i.e. center, etc.?

[Grit]

The center will be the matching Aerial Acoustics T series, as soon as it's released later this year. According to Michael Kelly (who owns/designs Aerial Acoustics), the center will have the same power-handling requirements as the 7Ts. So, I'm planning for that as my long-term center.

Presently, my center is a B&W HTM4 diamond, which I think the 9B is quite capable of handling (and isn't a great timbre match for my Aerial 7T's).

My surround speakers are a makeshift solution in this home.. they're one of B&W's in-wall speakers, and ironically a better match to the Aerial's. Once the rest of this stuff is settled, I may consider a better match for the surrounds, or wait until we buy a new house.

I only use the center and surrounds for movies and TV (no multi-channel music).

[Rod_S]

The center will be the matching Aerial Acoustics T series, as soon as it's released later this year. According to Michael Kelly (who owns/designs Aerial Acoustics), the center will have the same power-handling requirements as the 7Ts. So, I'm planning for that as my long-term center.

Presently, my center is a B&W HTM4 diamond, which I think the 9B is quite capable of handling (and isn't a great timbre match for my Aerial 7T's).

My surround speakers are a makeshift solution in this home.. they're one of B&W's in-wall speakers, and ironically a better match to the Aerial's. Once the rest of this stuff is settled, I may consider a better match for the surrounds, or wait until we buy a new house.

I only use the center and surrounds for movies and TV (no multi-channel music).

OK now I see why you seemed to be more concerned with the front soundstage and wondering about differences in the 4 vs 6 due to that upcoming Aerial center.

In my setups I always used the 4 to power my front L/R and the 6 for the center and either the surrounds or rears. I did this not because I could hear a difference but because if I wasn't listening in surround I didn't even need to turn on the 6 or the 2nd 4 (when I had 7 speakers). If you were to do the same thing then audible diffferences between the 4 and 6 wouldn't be an issue because the 6 would never be driving the mains plus you get the same power going to your center and have the same power on tap with the surrounds. Granted not a big concern now it would seem but could come in handy down the road should you choose to change the speakers. Wouldn't that make more sense in the end compared to the 4 and 9 combination where you would always have 2 channels of the 9 unused? I assume your 9 has all 5 channels as that's the only amp you have now.

[Grit]

Yes, I have all five channels installed. If I keep the 9b, two of them would power zone 2. Zone 2 isn't used all that often and I'd be quite content with a much lesser amp, since zone 2 is just ambient music outside.

The 6b/4b is a great solution. It probably more power than the surrounds need, but that isn't a problem. The real problsm is in available space. I have everything in a Salamander cabinet in the living room with closed front doors and some nifty, inaudible, filtered air for circulation.  That was the only way to meet the wife's approval, and a small restriction for her tolerance of my hobby. Unfortunately, it does limit my cabinet space. I can't find a way to squeeze a 6b and 4b in and have any reasonable room above each for airflow. The interior is only 20" heigh, and about 1.5" of that at the top has no airflow at the back (there's a lip in the back of the cabinet).

The 4b was amazingly cool. The 9b was MUCH warmer, even just in idle. I figure that's due to the orientation of the heatsinks. And if that's true, the 6b will need 3-4" of clearance.

I figure I can put a 4b and 9b in safely, or a 6b and a 2.5b.

[Rod_S]

That's too bad, being limited on space really sucks.

The 6 is an absolute monster, it's a big heavy chasis, is your shelf even capable of a 100lb amp? I don't find that the 6 gets to warm, certainly never hot, mine ony has about 1 cm clearance above (just enough for a finger to fit in) but it's in an open rack so airflow all around. That said though my 28's are out front on the floor and those buggers get really warm to hot(ish) but just turning on a fan on it's lowest setting and have the air pass over cools them down so much you can hardly even tell they are on.

The heat thing in general is interesting and inconsistent from what I have observed. There is a guy on another forum that switched out his McInosh amps for Bryston's and they were running so hot he had to move them out of the room and into a properly ventilated gear room. He then shortly after sold them for Parasound amps which run more in Class A then the Bryston's but were cooler. I have also come across some owners of 28's say they never run hot even without having airflow.

[servingko]

Another option would be to keep the 9 and 4 and add a PP300.  I ran five PP300's a number of years ago in my HT and enjoyed the sound.  Depending on the hit you may take on replacing your 9 with a 6, adding a PP300 may be a less expensive route.  I don't know if the PP300 received any of the "squared" series updates or not, but I did like the sound of them better than the 4BSST I also had at the time.  A bit more transparent with greater low level detail.  The form factor may not quite work for you in your equipment rack but it could be a viable center channel amp for you.

[Grit]

That's too bad, being limited on space really sucks.

The 6 is an absolute monster, it's a big heavy chasis, is your shelf even capable of a 100lb amp? I don't find that the 6 gets to warm, certainly never hot, mine ony has about 1 cm clearance above (just enough for a finger to fit in) but it's in an open rack so airflow all around. That said though my 28's are out front on the floor and those buggers get really warm to hot(ish) but just turning on a fan on it's lowest setting and have the air pass over cools them down so much you can hardly even tell they are on.

The heat thing in general is interesting and inconsistent from what I have observed. There is a guy on another forum that switched out his McInosh amps for Bryston's and they were running so hot he had to move them out of the room and into a properly ventilated gear room. He then shortly after sold them for Parasound amps which run more in Class A then the Bryston's but were cooler. I have also come across some owners of 28's say they never run hot even without having airflow.

Holy cow! Just 1cm? I have small fans providing airflow, and if you can get away with 1cm, I can probably make 2" work. The shelves aren't infinitely variable, so I'll have to test it out. The bottom shelf can hold 100 or 150, I forget which. The independent shelves hold up to 75 each. They all bold into an aluminum frame, so it's pretty sturdy.

If that all worked that just leaves the question about 2ch srereo... any idea if the 4b and 6b sound the same?

[Grit]

Another option would be to keep the 9 and 4 and add a PP300.  I ran five PP300's a number of years ago in my HT and enjoyed the sound.  Depending on the hit you may take on replacing your 9 with a 6, adding a PP300 may be a less expensive route.  I don't know if the PP300 received any of the "squared" series updates or not, but I did like the sound of them better than the 4BSST I also had at the time.  A bit more transparent with greater low level detail.  The form factor may not quite work for you in your equipment rack but it could be a viable center channel amp for you.

Is the PP300 the outboard mono block that's designed to mount to the speaker? I never considered it, but it's worth looking into. I wouldn't mind the center being slightly different as long as the power was sufficient.

[Rod_S]

Holy cow! Just 1cm? I have small fans providing airflow, and if you can get away with 1cm, I can probably make 2" work. The shelves aren't infinitely variable, so I'll have to test it out. The bottom shelf can hold 100 or 150, I forget which. The independent shelves hold up to 75 each. They all bold into an aluminum frame, so it's pretty sturdy.

If that all worked that just leaves the question about 2ch srereo... any idea if the 4b and 6b sound the same?

Yep, definitely about 1 cm, I can just fit my index finger in the gap but not my thumb.

To my ears I can't hear a difference between the two, mine are both SST C-Series (pre-SST2) and the other 4B which I no longer have was an original SST. I do hear some differences between the 4/6 and my 28B-SST2's though but it's not a slap you in the face very obvious thing whch I feel is a very good thing. Aside form the obvious extreme volume difference between them which would have the 4/6 clip while the 28's sing freely any notiecable normal listening condition difference is with low level listening where the 28's are very tight, solid, effortless.