Very interesting, curious as to what all is on that big PCB? Those caps are fairly low voltage, but with lots of high wattage resistors and heatsinks surrounding them, is it some kind of filament regulators? And possibly a high voltage supply at the very end?
Yes, about 3/4 of that board is dedicated to providing two regulated filament supplies for the 845, but doing it the right way! The resistors and massive number of heatsinked transistors spread out the thermal load nicely and keep the operating temperature of the components at about half their rated values.
The other 1/4 is our traditional high voltage supply, with individual shunt regulators for each channel.
The two small copper tubes are shielding for longer runs of signal carrying wire. The two fatter copper tubes hold our parallel feed capacitors inside, but suspended with damping rings to reduce resonance.
