B&K harsh sound


I recently auditioned in my system a used B&K 1430 amp, which is 3x200 into 8 ohms. I have monitor audio silver 5i speakers. My current amp is a rotel rb960bx, which is only 60 watts per channel. I almost couldn't listen to the B&K. It was so bright and a little ragged on the top end. Imaging was bad as well, both right to left and depth. Has anyone else had this experience with B&K amps? I wonder if it is just a bad match for the Monitor Audio speakers, or perhaps it is just this model. Should I give up on B&K for my system?
dsk
Thank you everyone. I am now wondering if I shouldn't give the amp another try. I actually wondered if it might take more than the 2 hours I gave it to come to life. But that's all the time I could spend with it. I should have left it in the system, even if I was just watching tv, and tried listening again after a day or 2. Someone asked about speaker cables. I am using Synergistic Research Alphas left and right and a new Wire World Oasis v center. I have heard others describe Rotel as having a "bright" sound. My amp does not come across that way, but on the other hand, I've been using it for years and years.
Sean has the right of it.

Let the amp burn in 24/7 for at least 2 or 3 days (don't power it off and on). Then see how it sounds. 2 hours is not enough.

I had a B&K ST1400 that your amp is based on and it was anything but harsh. In fact, the ST1400, like many MOSFET amps, was hardly the last word in transparency and "air", it was quite mellow and warm sounding, even slightly rolled off at the very top of the treble - IMO not necessarily a bad thing considering the speakers & front ends it's likely to be paired with.

Despite the howls from some quarters, I've found burn in to be a factor with most components. My CD player sounded OK out of the box but took about 200 hours (continuous hours, friend) to attain anything like its optimum sound. Bob Crumps power cords famously take a month to burn in. (But they're very entertaining/frightening meanwhile - it's like buying five different PCs in one.)

PCs can make a difference too.

Maybe the B&K was a defective amp or maybe you had a system mismatch. (Synergy is the thing in audio and, as pointed out, not all components mate well together.) Or maybe the B&K sound has really changed that drastically in the last 5 years. But I'm surprised the B&K sounded night and day different from your Rotel. Nevertheless, when all's said and done, you may simply end up preferring Rotel amps, or even preferring what you're used to listening through.
It could be that I am used to and enjoy the sound from my little Rotel. That causes a problem in the power department though. I clearly need more reserve power.