Hi Harvey, I too own a pair of CLS IIz. I purchased a pair of Krell FPB-250M monoblocks back in July. I have to admit to placing too much emphasis on reviews and not enough on my own listening tastes. I'm using a Pioneer Elite PD-65 for a transport, a Meridian 563 converter and BAT VK-5I preamp. I'm not getting the harmonic richness (liquidity?) that I would like and have a feeling the fault lies with the Krells. But then again, my front end very well could be at fault. I'm considering auditioning the Blue Circle BC-2 monoblocks. Based on what I've read at their website and the fact that the president to the company is using them with a pair of CLS IIz leads me to believe that this could be a match made in heaven. My best advice would be to audition, audition, audition. And buy an amp that has a low output impedance and good current output since the CLS IIz is a 4 ohm speaker that dips down into the 2 ohm area. By the way, have you auditioned any worthy subwoofers with your speakers? I've owned my Martin Logan since October and am ready for some real bass again! Good luck! Jim
