Special model made exclusively for use with the model J, K and N Gulbransen console.  Tibia channel tremolo switched on and off by switching between rotosonic drum and stationary 6×9 speaker.

Amplifier Type	4 Channel Vacuum Tube
Output Power	65 Watts total
Drum	Rotosonic
Horn	None
Speeds	1 Speed (Stop/Tremolo)
Interface	Custom