Marsh A400 vs Bryston 4B-ST

What is most critical in your decision is the interaction between the speaker and the amplifier. I own a 4B-ST and love it. And I am also an active proponent of the Bryston 20 year warranty (noted above) as well as the exceptional service and overall customer support provided by Bryston. As you may know, Bryston's resale value is also quite good. I also own a BP-25 preamp, and as others have indicated, there is something of a synergistic relationship between the amp and the preamp. Certainly, the combination is dead quiet. I can place my ear right next to the speaker and there is absolutely no hum or buzz. And the overall sound is accurate and dynamic and pleasant to listen to, without any trace of harshness. Prior to purchasing, I investigated both the A400 and the 4B-ST since we have no local authorized dealer for either brand within at least 400 miles. In so doing, I spoke to representatives of both manufacturers as well as a few authorized dealers. Ultimately, I selected the 4B-ST because of its ability to more easily drive lower impedance loads. In that respect, Bryston told me that it is more similar to the 7B-ST than the 3B-ST. The present iteration of the A400 is not as comfortable with lower impedance loads, a fact that I was informed of by the manufacturer. However, a dealer told me that a higher current version of the amplifier may be available sometime this year. Also, do not forget that Marsh can be purchased factory-direct if you have no local dealer; and there is provision for an in-home trial period.