I think the KAV 2250 is worthy of pairing with higher end preamps. I think it is an exceptional amp, you can pick one up used for about $2000 and I don't think there is anything in that price class that comes close. I have mine paired with a KRC-3 but I think a KRC-HR would be better, it's definitely good enough for the very best you have. I've also been curious what it would sound like with a Sonic Frontiers Pre 3?
It does not run all that hot for a Krell and is very comfortable to live with. I think this and the FPB 350M series amps are my favorite. I love the FPB 750MCX I also have but this KAV 2250 is so easy to deal with and has exceptional sound, very close to the FPB 750MCX amps. At normal listening levels you can easly hear it is something special and it is one of the best amps I've ever heard at low late night listening levels. It's so funny seeing people hear this for the first time with the B&W 801N speakers, they think of the amp as smaller and weaker and think of the speakers as bright and sloppy with the 15" woofers but together they are very musical and have a very dynamic, effortless sound. The mid-range is a little more predominant with this over my other Krell amps, but I don't want to exaggerate that, it is very subtle like a McIntosh in that respect. The bass is tremendous and very deep & TIGHT, it almost kind of shows off with the big B&W's on bass below 25 hertz, it can easily pressurize the room and you feel the big tight waves of bass filling the room and yet it starts and stops so quick. With this combo it's a physical thing you physically feel the notes from the midrange down, in your body, the couch and anything you touch in the room just like a live concert. Trebble and detail are far and away superior to my 300I (Krell Integrated) or Bryston 4BSST, more detail than any McIntosh. I feel like the imaging is somewhere between my FPB 300 stereo amp and the Mono FPB amps, up to it's power limit I don't know if I could blindly tell the difference between it and a Stereo FPB amp? The KAV 2250 is so good it should be the cheapest thing in the system, I really mean that. I think this amp was Dan's gift to the masses, bridged you have a 1000 watt amp into 8 ohms and 2000 into 4, it's a bargain if there is one in high end audio today. I use mine with all Silver Kimber Cables and in Balanced hook-up, it's just too good to use with Copper Cables. The only thing I don't like is the speaker connectors, they are the Euro plastic ones and are not as easy to work with.
The other thing to consider if you have the budget, the amp sounds better with 220V power on a 20amp circuit. On 115V it can blow a 15amp circuit breaker! The available Power makes a big difference. when you first plug it in expect it to take awhile to charge that big capacitor bank, mine took like 8 hours before it really started to sound good and strong.
Long winded here but I hope this helps and is accurate enough for you. If your on a budget, this is a wonderful amp, buy it and spend more on a preamp, source equipment and speakers you won't be disappointed. It does not sound like a tube amp but when you play SACD's and 192khtz X 24 bit files it can easily keep up with anything out there. It always sounds better than anyone expects it too, it sounds BIG and expensive.
