1950s Stromberg Carlson repeat coil transformer, similar to a WE 111c. This is a large and heavy transformer that was installed in a 1940s Daven audio test unit. Extremely well made and should sound great.  Tested with my Audio Precision test equipment this transformer is flat within +/-.5dB from 30Hz to 25KHz with a 40ohm, low impedance, load.

Pre-wired to spade terminals with the transformer strapped to 1:1, which can be easily changed to XLR connectors if needed.

Tested and guaranteed working.