ST-UBA2 Unbalanced to Balanced Amplifier

The unbalanced to balanced line amplifier shall be an RDL ST-UBA2. The unit shall provide one stereo unbalanced input, one stereo balanced output and one mono balanced output. The input shall be consumer line-level and the outputs shall be professional line-level. The mono sum output shall incorporate active mixing techniques.

The left and right unbalanced inputs shall have an input impedance no less than 10 kOhms. Two multi-turn continuously adjustable trimming controls, one for each channel, shall be provided to set the circuit gain to produce the rated output level for a line input level between -20 dBV and -10 dBV.

The unit shall provide an audio frequency response of 20 Hz to 20 kHz (± 0.2 dB) with total harmonic distortion plus noise of <0.02% (20 Hz to 20 kHz), intermodulation distortion of <0.004% and a noise floor exceeding 85 dB below the normal rated output level with an input of -10 dBV. Crosstalk between the left and right channels shall be less than 75 dB at 1 kHz and less than 60 dB for audio frequencies through 10 kHz. The unit shall provide headroom of no less than 18 dB above the normal rated output level.

The unit shall provide line-level balanced audio outputs at a nominal rated output level of +4 dBu with an output impedance of 150 O. The output circuits shall be configured to produce an unbalanced output of proper phase between the positive output leg and ground. Three outputs shall be provided, left, right and a mono sum of left plus right.

The nominal balanced output audio level for each channel, left and right, shall be displayed according to a VU average metering ballistic on two LED indicators with 0 dB calibrated to the rated +4 dBu line-level output. A green LED shall display a correlated linear minimum to maximum intensity for signal levels of -15 dB to 0 dB. A red LED shall indicate signals exceeding 0 dB. The unit must provide one meter for the left channel and a separate meter for the right channel.

The unit shall be constructed in an electrically non-conductive, thermally conductive enclosure. Internal circuitry shall be protected from moisture and vibration using a thermally conductive compound that permanently secures the circuitry within the enclosure.

The face of the unit shall provide graphical labels identifying wiring connections and operating controls. Indicators and controls shall be oriented toward the front edge of the unit.

Connection to external wiring shall be provided using a fixed terminal block on the edge of the unit. The terminal block shall accept wiring gauges from 14 to 22 and shall include a positive electrically conductive mechanism to prevent wire abrasion by the terminal screws.

The unit shall measure 3” (7.6 cm) x 1.6” (4 cm) x 0.7” (1.7 cm) and be compatible with all RDL STICK-ON mounting accessories. The unit shall be supplied with a two part re-closable polypropylene fastener system equipped with a rubber adhesive that bonds to low surface energy materials.

Power requirements shall be 24 Vdc ground-referenced with a maximum current not exceeding 75 mA. The unit shall utilize an external power supply. The unit shall be engineered, assembled and tested in the U.S.A. and be specified for continuous duty in professional installed systems. The unit shall be specified for operation in an ambient temperature between 0 and 55 degrees C. The unit shall comply with relevant EMC requirements and shall bear the CE marking.

The unit shall be an RDL ST-UBA2.