The FP22 is a battery-powered stereo headphone amplifier that provides headphone feeds from any audio input source. It has the unique capability of monitoring mono, stereo and mixed mono and stereo inputs. The FP22 monitors and combines these signals in the headphones without affecting the original signal. Stereo or mono headphone outputs appear on 1/4-inch phone or mini 3.5 mm stereo jacks. The FP22 can drive headphones to very loud levels. It is ideal for anyone in the broadcasting, sound reinforcement or audio recording fields who needs a flexible, high–quality headphone monitor.