Krell x-series, are ther any sonic benifits?

I wonder the same thing? I have a krell 600c and think personaly if they just gave themselves a honest power rating and put an x in the name. It is only slightly different cosmetics. Maybee the output devices are different, if so I'll bet there is a slight difference, but not much.

well I just sold my krell fpb 200c and I dropped it off at krell for the buyer to have the upgrade done and krell said there is a big diffrence between the two. If there was no diffrence why would they have an upgrade????????

Lev335: Why would they have an upgrade? How about the high end 2 channel audio business is dead, even more dead in this economy. How else can you squeeze money out of your customers if no one is willing to buy a new amp? AH UPGRADE FEES! I am not saying that nothing is done in the upgrade, I am saying that Krell created this upgrade to generate revenues. Why on earth would anyone buy a new amp when they could come here and buy them discounted or slightly used for 50% off?

I would tend to agree with Ericbee - Krell did it probably for marketing purpose. Looking at the specifications the entire new line of amp have the same weights and dimensions as their predecessors, yet they are each 100W more powerful. Since the size of the heak sink stays the same, one may assume that the number of power transistors also remain the same. So how do they squeeze the extra power out ? Perhaps by adjusting the operating region ? The amp may sound better than the replaced version but I suspect the improvement may be subtle. As always, the only way to find out is to do a side-by-side comparison. Has anyone done that yet ?