he 258 is used with the 257 and was designed exclusively for use with Thomas organs.
Below is a description by Harvey Olsen from the “HamTech Mailing List”:
“It is the “complex-wave” cabinet for the above system [257/258 pair]. It has two 147-type power amps (with 9-pin inputs) that drive the 15″ bass, and two stationary 12″ speakers. As with the 257, the amps are easily rewired but there are no crossovers or rotors, and nothing spins.”
