From Rain City Audio:

This rare early-production Bose® 901 Active Equalizer, serial #9724, came through the shop recently for an overhaul. It’s owner reported that both channels would cut out intermittently, the switches were noisy, and the power lamp was flickering. In other words, the standard age-related issues! Nothing a full overhaul can’t fix.

This equalizer looks like it may have been serviced in the past, replacing many of the transistors, and a handful of the electrolytic capacitors. Otherwise, though, it looks all original.

With all new parts, and a thorough control cleaning, this equalizer is back as good as new! It’s going to sound great for a long time to come, too.