Krell FPB 600 or 250M's?

I agree with Kirk930, I have owned all of the FPB series. Other than space and price ( fpb 200 vs 250) Mono blocks are the way to go! Separate power supply to each speaker and shorter cable run for less interference (are just a couple of the benefits). The best speaker cable is no speaker cable at all. So by shortening your cable run to Below 1m has neat benefits. Last but not least there is zero stereo cross talk.  
  

The only difference (I'm told by Patrick at Krell) between the mc and mcx line is "cast", that's it. If you are not using cast (other than Aesthetics) a mc and a mcx are the same amp. 
Krell and most reputable High-end brands work really hard to have "a brand type" and furthermore a "line or model type". This would not exclude a certain sonic signature that you should expect out out of a model line. A 250mc should have the same sonic signature as a 750mc.
As a current owner of 8 Krell amplifies and the previous owner of dozens before this is what I found this to be true. 
I can't speak on modified amps as I have never owned one, most manufactures don't recommend it, and I'm a bit of a purest to the to the original engineer's design philosophy.
Of course weather YOU like a line/model personality is subjective, what blows someone else away might only be meh to you.  

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