Krell FPB 600 or 250M's?

Strych2, I agree with you on the mono-block is better,  shorter speaker cable's,  however,  to be clear,  the 250 m is bright sounding with most high quality revealing cable's,  where the 600c or 700 is extremely better in every way with any cable's,  the only thing that would beat this out is 650m or 750mcx,  as a matter of fact,  the 700cx is better than the 650m!, the cx line is a total different animal in sound than the original or c model's of the fpb line,  I know, I have owned many, and my ride off into the sunset amplifier is the only krell modified 700cx anywhere,  I spent  $11,000.00 with up grades that will blow a stock 750mcx out of the water 😎

doug2507, do what you like,  my opinion is the 600 over the 250m, cheers 

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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