The Yamaha BK-4B is an electronic organ featuring three keyboards: two manuals with 44 keys each and a pedalboard with 13 keys. The instrument includes tone levers for various voices, controls for vibrato, sustain, and reverb, as well as a unique Spacious Sound function that simulates a revolving speaker effect.
| Pedal Keys | 13 keys (1 octave) |
|---|---|
| Power Consumption | 40 Watts |
| Weight | 55kg (121 lbs.) |
It produces a feeling similar to a revolving speaker using Yamaha's exclusive electronic circuitry.
There are 5 voice levers available for the upper manual.