McIntosh MA6900 vs MA2275 for Rock Music

I have the both MA6900 and B&W804s which I bought new a "while" back after an extensive listening campaign covering a range of amps, including Krells, and several high-end speakers including other B&Ws. I can tell you I *love* the combination for all types of music, including loads of rock. The key to your decision is how loud you like your music. The 804s pull a lot of current, especially when the bass drops down to 3 ohms. I regularly run at sustained 20 watts and, at parties, 100 watts. The solid state MA6900 will deliver unlimited current and stay cool if you run off the 4 ohm posts. The Mac tube amp will sound beautiful at cocktail party volume but I am skeptical you will be happy with the bass at loud volumes. Listen and tell me what you decide! One other tip - you need a good source to get enough bass out of the 804s. I changed to a better DAC (Musical Fidelity V90, under $300) and that made all the difference versus a computer or pretty good CD player.

And I have owned the MA2275 and it is a wonderful amplifier, but it is still a 75 watt tube amp and is not ideal for every speaker with all genres. I totally loved the amp, and I used hard to drive Dynaudio Focus 160 speakers, but it got very soft, extremely pleasant to listen to, but the attack and last bit of punch and "start-stop-bass" was missing, especially in rock music. I didn't listen to the MA6900 though and cannot give any information about how the compare. McIntosh feels great to have in your home. Good luck!