B&K ST-140 vs 200.1 mono blocks


I currently had a B&K ST-140...the last version with blue and red lettering, have them on a pair of Castle Inversion 100 speakers 8 ohm, preamp is Melos Reference MA-333, it sounded wonderful with "tube" like sound. Just wonder how will the B&K 200.1 mono blocks compare to the ST-140? You advise and opinion much appreciated!
pioneer48
I believe Unsound has provided you with good info. When considering an upgrade it is best to have defined what improvement one is looking for. If you are happy with the 140 and it drives your speakers to your satisfaction then keep it. Enjoy!
Thank you for all the responses so far; I heard comments that the ST-140 produce more tube like sound...and I feel the same way too. Moreover, I don't really have a big listening room, so may be better off stick with the ST-140 instead of going for the more powerful 200.1 mono blocks!
I've had the B&K ST-140 and M 200 mono blocks (not the 200.1s)in my system, and IMHO they are very different amps. The cap coupled ST 140 is warm, rolled off in the highs and a bit mushy in the bass, the DC coupled M 200's were cooler, more extended with tighter bass, much more authority and capable of handling lower impedances much(!) better. BTW, due their somewhat low input impedance, neither is really a great match with most tube pres with their typical high output impedance.
I don't know but I had a B&K ST-202 which is the same design as the 140 just more powerful with another set of FETS. I upgraded to a Crown XLS 1500 class D drivecore amp and love it. The old B&K is an excellent amp so it depends on what your driving and your own ears too. The mono blocks should be an upgrade but with a S/N of about 97db for the B&K's and 103db for the higher power and flat clean response Crown at the same price or less you should check them out. I wouldn't try to drive particularly efficient speakers with any of them but they all should sound great under about 100db. The higher damping factor and power of the crown just seems to bend the drivers of my old NHT 3.3's to its will.