No more big power supplies for preamps

That "air" may be serving a good purpose, namely preventing different parts of the power supply from interfering with each other. Here's shot of the inside of my preamp power supply, I purposely designed it to keep the B+ supply (front and right side) away from the two high amperage filament supplies (in the back). The B+ transformer and rectifier tube are on the top of the box, so not in the picture.

26 Preamp PS

A "half full" chassis could be a very good sign and indicative of a simple straightforward circuit. You can have a robust power supply coupled with a simple circuit with fewer parts that are of exceptional quality.

Ait, nice job on the preamp! Love to see the rest of it.

Agree with Bill, it's attractive and looks well built.
Congratulations, I'm sure it sounds wonderful.

Sure, if you insist ;-)

26 Preamp

The rectifier tube is a 5Y3G, the preamp section uses balloon 26 and 0A3 and 0D3 gas voltage regulator tubes. The "output transformers" are Bent/Slagle autoformers in parafeed, so they do double duty as volume controls on the output. Remote control of volume and balance are nice as they let me lock in the perfect levels from my listening position.