Description
The ST-UBA2 is a two-channel unbalanced-to-balanced line amplifier that converts consumer-level signals to professional +4 dBu outputs. It accepts unbalanced sources such as CD players, cassette decks, computer sound cards and televisions. The module provides low-noise balanced outputs suitable for professional patch bays and monitoring systems.
Each stereo channel features independently adjustable gain from 2 dB to 22 dB and a summed mono output for subwoofer or mono monitoring connections. Dual-LED VU metering is provided for both left and right outputs to assist level setting and signal monitoring. The green LED indicates a range beginning 15 dB below +4 dBu and the red LED indicates +4 dBu peak.
Audio performance is specified with THD+N below 0.02% across 20 Hz to 20 kHz and IMD under 0.004%. Frequency response is flat within ±0.2 dB from 20 Hz to 20 kHz and noise is specified at less than -85 dB referenced to +4 dBu. Crosstalk performance is better than -75 dB at 1 kHz and better than -60 dB at 10 kHz for clean channel separation.
Connectivity includes two unbalanced line-level inputs with 10 kOhm input impedance and three balanced +4 dBu outputs (left, right, mono sum) with 150 Ohm output impedance. Input signal range is intended for consumer outputs in the -20 dBV to -10 dBV range and headroom exceeds 18 dB above +4 dBu. Power is ground-referenced 24 Vdc at 75 mA for integration into standard RDL powering systems.
The ST-UBA2 fits installation needs in broadcast racks, AV racks and field carts due to compact packaging and compatibility with other RDL modules. The mono sum output can feed monitors or subwoofer amplifiers while balanced outputs interface with professional consoles and recorders. Metering and adjustable gain simplify setup in mixed-signal environments.
The module is engineered for reliable audio conversion with robust analog circuits and low distortion components. It operates in ambient temperatures from 0° C to 55° C and ships in a compact cardboard package. The ST-UBA2 offers a straightforward solution for converting unbalanced consumer-level sources to studio-grade balanced outputs.