well paul, the bel amp is a one of a kind and everyone who has heard it loved it for its uncomplicated and robust nature. not exactly a tube but as close as one could get with the benefits of ss, wider bandwidth, less distortion and more control. i wish is had 2 of them.
about the master upgrades i hear you. at $225 each or $1350 for the 6 caps, they better be something. but in the bam, the entire signal goes them so they do what they are supposed to do. in the case of the rc network, since they are a termination for the amp providing a 10 ohm load at 100 khz, it makes sense to me that the amp being terminated with a better sounding termination sould make the amp sound as good as it can. imho, copper being better sounding than aluminum.
hope you are well.
bobby at merlin