Sorry if you've already read this in some other posts, but I have some experience comparing these two brands (but not the models, so YMMV). I compared the MC402 to Pass Labs x250.5 and xa30.5. On my Thiel 2.4s the Pass amps easily outclassed the similarly priced Mcintosh. The 402 had been used by the previous owners of my 2.4s, and he'd loved it, so it could be enjoyable, but both Pass amps had more of everything Bo mentioned. I eventually settled on the XA model, as it was the more natural of the two Pass amps on my speakers.
Mcintosh mc601 vs Pass Labs XA 100.8
I have a mcintosh mc-601 monoblocks amplifiers, I have a dynaudio c4 confidence speakers and ayon cd5s cdplayer, I want to buy a new amplifier, a Pass Labs XA 100.8 POWER AMPLIFIER is a good options? Is a upgrade in relation to the macs 601?