Bell and Howell Tube Mixer, Preamplifier, 12ax7, DIY Lunchbox? Simpson VU Meter!

Description

Here is a rare bird that I picked up locally and thought about retro-fitting into a little preamp with the cool Simpson VU meter. I am a big fan of having preamps close to the source and running my signal at line level, so I thought I would do something like that with this, but never did.
Looks to be an old mixer, maybe specifically for a headphone mix? Your guess is as good as mine, my research came up with nothing.
Great looking case and some high end components, could be turned into something, or trace the circuit and restore it to its original glory! Please look at my other listings as I downsize to a smaller studio, thank you!