08-25-2014, 11:48 PM
That speaker looks mighty strange. It appears that someone installed a smaller modern speaker underneath the original and rewired it to the original output transformer. The loose wire looks like it is the one that went to the voice coil of the original speaker which is no longer functional. Except for its field coil which is still being used as a power supply choke, the rest of its voice coil wiring is disconnected.