I know this thread is old and you bought the McIntosh MC 501Mono blocks I wonder if you are satisfied with the 501Mono blocks? I have owned mine for 15 years back then I was driving B&W 802N Speakers and before I bought the Mac's I owned a Krell 600c ,I've been very happy with the McIntosh 501Mono blocks they still sound fantastic! Now I have Sonus Faber Amati Homage speakers with ModWright LS 36.5DM Tubed Linestage a killer combination, it's funny I called McIntosh about replacing the caps the rep told me wait about 15 more years! I asked him about the new 611 he said hang on to the 501Mono blocks there way under rated. Happy listening my friend!
