Active Sender / Distributor-Twisted Pair Format-A-Three audio inputs to Four outputs

Ideal Use Cases

The RDL RU-TPS4A is designed for audio systems that need to place three line-level signals on RDL TP Format-A and make those signals available to as many as four receivers. It accepts balanced or unbalanced line-level sources through a detachable terminal block, with the three inputs assigned to Format-A signal pairs A, B, and C. Each of the four RJ45 outputs can drive RDL TP Format-A receivers.

This configuration is suited to installations that require the same three audio signal pairs at multiple receiving points. The distributor also powers all connected receivers, centralizing signal distribution and receiver power within one module. Its support for high-density rack mounting with RACK-UP accessories makes it appropriate for equipment racks where multiple distribution modules need to occupy limited space.

Why Choose This Model

Each input pair has an adjustable multi-turn front-panel trimmer with a specified gain range of 4 dB to +18 dB. Three dual-LED VU meters display the level of the three signal pairs, giving the operator a direct front-panel reference while making adjustments. A blue power LED confirms that the module is receiving dc power.

The RU-TPS4A incorporates 11 indicators in total: one Power In indicator, four Power Out indicators, and six LEDs forming the three dual-LED VU meters. Rear-panel LEDs indicate correct output voltage at the RJ45 connections. These indicators provide visible confirmation of input power, output power, and audio levels without requiring access to external monitoring equipment for basic status checks.

Installation and Integration

Balanced or unbalanced line-level sources connect through the detachable input terminal block. The three inputs have a specified 20 kΩ balanced input impedance. Format-A receiver connections are made through four RJ45 output jacks, with signal pairs A, B, and C used across the system.

Power connections consist of two power jacks and a detachable terminal block. The module requires 24 Vdc at 120 mA plus the current required by connected loads. Recommended power supplies are the PS-24AS for the USA and PS-24AX for international use; the power supply is not included. An integrated power bus provides expansion to adjacent distributors.

The module measures 5.8 inches wide by 1.7 inches high by 3.25 inches deep, equivalent to 15 by 4.3 by 8.25 centimeters. Its specified ambient operating range is 0°C to 55°C. These dimensions and the available RACK-UP mounting accessories support compact, high-density integration.

Performance Highlights

The RU-TPS4A has a specified frequency response of 10 Hz to 50 kHz within ±0.1 dB. THD+N is listed at less than 0.005%, while headroom above +4 dBu is greater than 18 dB. The stated noise figure below +4 dBu is less than 90 dB.

Specified crosstalk is less than 90 dB at 1 kHz and less than 75 dB from 20 Hz to 20 kHz. Common-mode rejection is greater than 80 dB from 50 Hz to 150 Hz. Together with individual pair-level adjustment and the three dual-LED VU meters, these figures provide defined operating references for configuring the distributor within a Format-A audio system.

What Makes It Different

The distinguishing feature of the RU-TPS4A is its combination of active sending, four-output Format-A distribution, receiver powering, and individual monitoring for three audio pairs. One module accepts three line-level inputs, assigns them to pairs A, B, and C, and distributes them through four RJ45 outputs while powering the connected receivers.

Front-panel level trimmers and VU meters address setup and monitoring, while rear-panel voltage indicators address output-power status. The adjacent-module power bus and RACK-UP accessory compatibility extend the same design into denser installations without changing the module’s core three-input, four-output arrangement.

Final Assessment

For an RDL TP Format-A system requiring three balanced or unbalanced line-level inputs at up to four receiver locations, the RU-TPS4A provides a clearly specified distribution point. Its adjustable gain, dual-LED metering, four powered RJ45 outputs, wide stated frequency response, and compact rack-compatible enclosure cover both signal management and installation requirements. System planning should include the 24 Vdc supply and the current demands of connected receivers because the recommended power supply is sold separately.