Leslie Model 257

Basic Specifications

Amplifier Type
1 Channel Vacuum Tube
Output Power
40 Watts
1 – 15″ Speaker
1 – Compression Driver
3 Speed (Chorale/Stop/Tremolo)

Additional Information

The 257 is used with the 258 and was designed exclusively for use with Thomas organs.

Below is a description by Harvey Olsen from the “HamTech Mailing List”:

“The 257/258 dual cabinet system was actually for selected, high-end, 60s vintage Thomas Organs.

The 257 was used for the flute and tibia voices. It’s essentially a 247, but with a nonstandard 9-pin input for Thomas. If you run into a 257, the 6550 power amp is easily rewired to 6-pin, 147 specs.”