Originally Posted by mb3k
It looks as though it comes a tad short to fit snuggly in the hammond case (ie. the pcb touching faceplate to faceplate). I haven't followed the MHMax at all but maybe it could be made longer?
Yes, you are correct - it's about 3/16" short. I believe cetoole did this to make room for his Noble pot without pushing it too far back into the heat sinks. When using the Alps and the Neutrik PCB jack, though, that extra space will really help pulling all the test points up from the bottom of the board. We'll have to get cetoole's take on it for the real reason, though.
This one verified the circuit and final layout for the DB's. We're hoping we have a configuration for the MOSFET's, too - NeilR is working on those with Bperboy as another test case (he was first, actually). The structure, thickness, and perhaps the final length may change some to put it jam up against the endplates, but nothing will alter enough to change from this case.
The good news is that I used the DB option - the 2SC3422/2SA1359 pairs, and everything worked - the first time out!! I've never had that happen. Everything biases like a charm:
Walwart: 24VAC, 35VA ($6 surplus Basler Electric)
Tube Bias: 13.5 (12AE6A GE)
DB Bias (2SC3422/2SA1359): 109.5mV!!, +or- 0.2mV all four ~50ma ea.
EDIT: Prior to firing it up: