The B9 Organ Machine Pedal from Electro-Harmonix transforms the tone of a guitar and/or keyboard into that of a full body electric organ. The nine presets are tuned to emulate some of the most popular and classic electric organ tones. The B9 provides control over percussive attack level, modulation speed, and organ and dry volume. The tracking on the B9 can keep up with quick musical passages.

It is recommended to place the B9 first in an effects chain. Modulation, delay and reverb effects should be placed after the B9. The unit will not perform well if placed in the effects loop of a guitar amplifier. It performs best using the bridge pickup of a guitar. If a guitar's pickup has a weak output, performance can be improved by putting a clean boost or a compressor in front of the B9. It is not advised to place a distortion or overdrive in front of the B9. This will muddy up the input signal and cause the tracking to be unstable. If overdrive or distortion is desired, it is best to place it after the B9.

A compressor in front or after the B9 can help smooth out uneven peaky frequency response that may cause some sounds to be over-accentuated in some guitar amplifiers. The B9 was designed to be used with a guitar and can be used with a bass guitar. The organ sound will not be heard above the 23rd fret. Below the C note, third fret on the A string, performance is compromised.