Is that the filament trafo I see in the center of the case? If so that's a bad location for it, right next to the output of one of the beta channels. Of course in that chassis there's no good location for it so eff it. And Gary, if I were you I'd get busy with the drill and start perforating much of the open space in that bottom panel, you're not going to get much airflow the way it is now.

yes, what Nate says - let her breath , gale forces may be called for ..dB

Heh, big holes under each board. Full step bit big holes, two under each Beta board and under each EHHA board. It is getting good ventilation where it needs it and the top has a set of large holes too with added space between the top and the marble slab.

I'll be upgrading the S22 sinks (plenty of space) and I bought a metal box to place over the heater transfo. It's quiet already but more shielding never hurts

I'll be keeping a close watch on it.

Don, yes I did try the 800 on the EHHA. It's very good but not my thing. There's something about the anonymity of it's sound that left me feeling very neutral about it. Not enough heft in the bass either.