The EZ-HDA4B contains four stereo headphone amplifiers with individual front-panel volume controls. Headphone outputs are provided on rear-panel MINI jacks. One stereo input signal feeds all the amplifiers. Stereo RCA jacks, a MINI jack and a 1/4" jack are provided for connecting the input source. The EZ-HDA4B is used in music stores, houses of worship, studios, museums, home component systems and commercial sound systems.