Mdconnelly,
Good question. When I heard my specific Reference 8B amps on the 10T's it was at a friend's home who is a member of the Phoenix A/V club. He has a wonderful setup and a fantastic, custom-built room that is almost perfect for audio, judging from my experience that day.
The one area that came off as lacking on the 8B's compared to the owner's modified Bryston 7BST's and the Rowland 201's was that of bass extension -- weight and slam. Both of the higher-powered amps beat the 8B's in that regard. But you also need to put it in the context that the 8B's were being used on relatively inefficent speakers ( 86 or 87 dB/watt, I believe) in a large room and at relatively loud playback levels. Still, the 8Bs acquitted themselves quite well although rated at less than half the power of the other amps on hand. Actually, I couldn't believe how loud the 8Bs played that system while maintaining their composure and ability to make music.
In my own system, on the VMPS RM30s, I also find the Reference 8 series a little light in bass extension compared to other amps I have used. Now the Reference 9's have considerably more rms power output capability than the Reference 8's, and they have more instantaneous peak power capability to boot.
That said, the 90dB/watt RM30's in my room are much easier for an amp to drive than my friend's 10T system. But, at even modest listening levels, the Reference 8's come off as being somewhat anemic in the lowest bass. There is no denying they are dynamic and extremely articulate in the bass they provide, yet the Reference 9's in my system sound more relaxed at higher average playback levels that the Ref 8s could comfortably manage. Perhaps more importantly, the Reference 9s provide real weight, slam, and extension in the low bass. I found early versions of the Reference 9s not quite up to the midrange/treble performance of my updated Reference 8s, in terms of speed, incisiveness, and hf extension. However, the 9.02 version of the Reference 9 with the double input capacitance (and yellow output caps removed) appears to surpass my Reference 8s in the midrange and treble, and it's a bit more holographic in its soundstaging presentation, as the TAS reviewer noticed.
If you own 10t's or any other relatively inefficient speaker, and enjoy healthy bass slam, then there is no question that the Reference 9.02 amps are the way to go.
On the other hand, a person who uses monitors, with limited low bass or someone who augments their main speakers with powered subwoofers could be very happy with either the Reference 8s or Ref 9s, I should think.
Frank :)
