Power supply, remote handset and a motorized pot may get you all thinking.
A single pair of IC's and a clear view with the binding posts showing resistors across them might help a bit. FWIW.... the value of the motorized alps is 10K and only two terminals are being used. Those two terminals are connected (4 terminals total) and in parallel with the 4 terminals of the binding posts and the 4 terminals of the RCA's
so what the hell is this thing for?
OK.... Edit after 4 comments. Martin G nailed what it is but my intended application is still the mystery. the Key factor is adjustability from the listening chair. In many instances it wouldbe used with these.