From the Rain City Audio Repair Blog:

Another classic Bose® Active Equalizer came through the shop recently for a standard overhaul from sunny California. It’s owner reported that it was performing poorly and channels would cut out. Sounds like a good time for a rebuild!

Inside, it looks like 6 of the 7 secondary filter capacitors and one channel’s output capacitors were replaced in the late ’70s or early ’80s.

This unit got all new parts, including silver solder, film output capacitors as an upgrade from the electrolytics, and a thorough cleaning.

The indicator lamp was flickering, so it too was replaced with a new neon bulb to illuminate the power switch.

Fully restored, this Active Equalizer is going to be a fantastic performer for many years to come!