Stereo Audio Distributor-2x4-Phono Jacks

The RDL RU-UDA4 is a stereo unbalanced audio distribution amplifier designed to route each of two input channels to four outputs. Two phono input connectors and eight phono output connectors provide four outputs for the left channel and four for the right channel. Both channels operate at unity gain, preserving the nominal signal level through the distribution path. The channels may also be used independently as two separate mono amplifiers, giving the unit flexibility beyond conventional stereo distribution.

Ideal Use Cases

The RU-UDA4 is suited to systems that need to distribute a stereo source to as many as four stereo destinations through unbalanced phono connections. It can also support two independent mono distribution paths, with each input feeding four corresponding outputs. This arrangement is useful when a single audio signal must reach multiple connected devices without requiring a separate distributor for each channel. Its standalone and rack-mountable design supports both individual installations and systems that group multiple modules together.

Why Choose This Model

This model combines straightforward 2-by-4 stereo distribution with documented audio performance. Each channel has a 10 kΩ unbalanced input impedance and feeds four outputs with a 100 Ω unbalanced output impedance. Unity gain on both channels makes the RU-UDA4 appropriate when signal distribution is required without a nominal gain change. The ability to separate the left and right channels into independent mono paths also makes the unit adaptable to different routing requirements.

Installation and Integration

The RU-UDA4 may be operated as a standalone component or incorporated into a rack-mounted system. Its one-third-rack format supports high-density rack mounting when several compatible units are installed together. Connections are made through two phono inputs and eight phono outputs, so the complete stereo configuration provides four outputs per channel. The unit requires ground-referenced 24 Vdc power at 25 mA. A power supply is not included; the specified recommendations are the PS-24AS for USA use and the PS-24AX for international use. The supported ambient operating range is 0°C to 55°C.

Performance Highlights

The specified frequency response extends from 5 Hz to 50 kHz within ±0.5 dB. THD+N is rated below 0.020%, while the published noise specification is below -90 dB, referenced below -10 dBV. Headroom is greater than 28 dB. Crosstalk is specified below -90 dB at 1 kHz, below -80 dB at 10 kHz, and below -75 dB at 20 kHz. Together, these specifications define the RU-UDA4 as a distribution unit intended for dependable audio performance across a broad frequency range.

What Makes It Different

The RU-UDA4 places two complete four-output distribution paths in a one-third-rack module. Unlike a configuration limited to paired stereo operation, its left and right channels can function independently as separate mono amplifiers. That means the same unit can handle one stereo input distributed to four stereo destinations or two unrelated mono inputs distributed to four outputs each. Its combination of phono connectivity, unity gain, and standalone or rack-mounted operation creates a focused solution for unbalanced audio distribution.

Final Assessment

For systems requiring stereo unbalanced audio distribution through phono jacks, the RDL RU-UDA4 provides a clearly defined signal path: two inputs, four outputs per channel, unity gain, and eight outputs in total. Its independent-channel capability expands the available routing options, while the one-third-rack form factor supports compact, high-density integration. With published specifications covering frequency response, distortion, noise, crosstalk, headroom, impedance, power, and operating temperature, it offers a well-documented choice for two-channel or dual-mono distribution.