so interesting things popped up when the Ampzillas were inserted - they actually blew a fuse within 10 minutes playing music. Blew several more when lifting grounds with no signal even. Certain bassy music also showed faint flashes of the peak LED lights.
It appears to stem from an outlet to the right of the fireplace I have used for monoblocks. After a sack of fuses, going through several pointers from
@Folsom including checking polarity, taking out the +6 gain on the TVC, lifting grounds, moving all to the "left" outlet, and even taking the TVC out of the chain and only using the MSB - finally came to some interesting conclusions.
first, the outlets are on different circuits and don't have grounds. although
@213Cobra checked polarity and ground with an ifi product and both outlets yielded the same results. however, putting everything on a power strip to the "left" outlet - there hasn't been a blown fuse since. so these two circuits clearly don't play nice with each other. lifting the grounds now doesn't blow fuses unlike the original setup.
i think this is why the other fully balanced amp we tried - the ARC Ref 160- was having some squirrelly issues as noted above. the Luxman is not fully balanced and was on the left outlet to begin with as a stereo amp. i should also note that there was no difference between MSB and TVC as preamp from a peak power point of view.
what I can say about the Ampzillas after 48 hours of run-in is that they don't congest on crescendos and seem to have quite a bit of power in reserve - even though the lights flash once in a while. they have really opened up since inserted and the top end is quite nice, the midrange tonally warm and bass that is full but not slow. in short, they seem to drive the speaker quite well and sound promising. I won't make full judgment until 100-200 hours or so is on them as they continue to change.
i am going to have a conversation with the manufacturer tomorrow about the sensitivity of the peak light - we are assuming its a milli-second type soft clip and nothing harmful. what this all leads me to (still) believe is: YG loves power.