The RB-UL1 is a single stereo unit for interfacing domestic or semi-professional unbalanced equipment, such as a CD player, to professional balanced line levels.
The two RCA unbalanced inputs have an impedance of 10k Ohms and are routed to two balanced XLR-3 outputs with an output impedance of <50Ω. The output gain can be individually adjusted for left and right channels by using pre-set potentiometers accessible through the rear panel.