your point concerning the peamp generalizes to the question of system synergy - to be sure, but nevertheless in noting the "20-30% improvement" you seem to be speaking about the SST2 as such, taken for itself. I am curious to know what the characteristics of the SST2 are that make up the improvement ratio, and in what way they better the earlier SST performance
By the way, I do run a BP26 line as well as a Prima Luna tubed preamp (which is just wonderful both with Nuforce Ref 9 V3 SE and a little known power amp from the UK, the Alner Hamblin SA400)
I answered your questions in post/s in the past. I'll try to recall what I wrote.
First of all I have an unconventional multi-channel stereo setup. I primarily listen in multi-channel stereo with the Yamaha 7 channel enhancer engaged.
Prior to getting the 3B SST2 I was listening in 2 channel pure direct with the 3B SST, which was very good. When the 3B SST2 arrived, I was planning to do a direct comparison. Faced with the daunting task of sorting out all the jumbo of wires. I said the heck with it and just swapped the amps around.
I placed the 3B SST2 on the fronts for which I have two sets of speakers hooked to it. Moved the 3B SST to surrounds and 3B ST to front and rear channel.
Right off the bat I could discern a noticeable difference in bass resolution. It wasn't a marginal difference that I needed a db test to confirm. The bass was articulate to live like sound of a bass guitar in a bar setting. And it had what I called vibe, I could feel the vibe. Also apparent was the controlled highs, particularly through my B&W 602 S3, which before could be described as harsh with glare. But now that was gone. Less noticeable was improved midrange and highs, which became more apparent after adjusting to the new sound over the coarse of a few weeks. Yet the SST2 still retains the Bryston sound of previous amps.
Then it became apparent the SST2 was processing details the SST wasn't, played through the BCD-1.
So I tried to put a percentage estimate on the sound improvement, I was hearing in multi-channel stereo. It wasn't a marginal difference, nor was it a whole new sound. Just improved resolution on the SST, which I pegged around 30%. However as you are probably thinking, part of the estimation is skewed by improved bass performance on the surrounds, which is partly true. However I spend over 30 hours a week listening and quite sure the attributes belong to the SST2, which I wasn't hearing prior to that.
In two channel pure direct mode on the Yamaha av/receiver, I preferred the SST over the SST2, because as I mentioned the bass was boomy. Which I don't hear in multi-channel mode.
