The Q4TR is a line transformer unit, specifically designed for use in combination with the Q4 four-channel power amplifier. It transforms the Q4 amplifier's low-impedance 4-ohm speaker outputs into speaker signals for use in constant voltage audio distribution systems such as 100V, 70V, or 50V systems. It features 4 separate audio line transformers with a total power rating of 4 x 600 watts, and the transformers have sockets for 100V, 70V, and 50V applications.