in good working condition.

From BBE:

The BBE 422A is an intelligent audio processor designed to solve a series of complex problems as described in the previous section. It is, however, very simple to set-up and operate and once installed will function flawlessly without further attention.

It is a dual channel, rack-mountable device for use in -10dBu unbalanced line level applications such as those found in semi-professional and musical instrument applications. The BBE 422A takes up one EIA standard rack space of 19 inches width and 1.75 inches height (1U). There are two separate channels to allow for either full stereo program or two independent mono channels: A house P.A. mix feed for one channel and the stage monitor feed for the other channel.

BBE® applies different phase correction algorithms to three separate frequency bands. The variable front panel control allows the user to adjust the amount of process desired.