RDL RU-MLB4P Mic/Line-Level Bi-Directional Network Interface, 4 line PoE

Ideal Use Cases

The RDL RU-MLB4P is suited to networked audio systems that need bidirectional conversion between local analog audio and Dante. It converts four microphone-level or line-level sources into Dante audio channels while simultaneously converting four Dante channels into balanced line-level outputs. This 4×4 configuration is useful wherever microphones, analog source equipment, amplifiers, or other line-level devices must connect through a 100 Mbps Dante network. Individual rear-panel MIC or LINE selectors allow each of the four input channels to be configured for its connected source.

Why Choose This Model

The RU-MLB4P combines four analog inputs, four balanced analog outputs, Dante networking, microphone gain, P48 phantom power, and PoE capability in one compact interface. Automatic gain provides 40 dB for condenser microphones and 60 dB for dynamic microphones. P48 phantom power supplies 48 Vdc in accordance with IEC 61938:2013. The interface supports 24-bit audio at 44.1 kHz or 48 kHz, with 48 kHz used as the default sample rate. Its specified audio operating reference is 18 dBFS at +4 dBu.

Installation and Integration

A Dante connection is provided through an RJ45 network connector with dedicated Link and Speed indicators. Analog inputs and outputs use detachable terminal blocks, supporting secure connection within a permanent installation. Four balanced outputs operate at a nominal +4 dBu, with an output impedance of 150 ohms balanced or 75 ohms unbalanced. Power can be supplied through Class 0 IEEE 802.3af PoE or from a 24 Vdc source. The stated DC requirement is 180 mA plus connected phantom-power loads. Separate power jack and detachable terminal-block connections are included. Recommended supplies are the PS-24AS for the USA and PS-24AX for international use.

The unit measures 5.8 in. wide, 1.7 in. high, and 5.2 in. deep. Its specified ambient operating range is 0 degrees C to 40 degrees C. Thirteen indicators provide visual status for power, four output signals, four input signals, Dante system and synchronization status, and Ethernet link and speed.

Performance Highlights

The RU-MLB4P covers a frequency range of 20 Hz to 20 kHz within ±0.5 dB. THD+N is specified at less than 0.1%, while noise below +4 dBu is below -70 dB. Common-mode rejection exceeds 70 dB from 50 Hz to 120 Hz. Crosstalk is specified below 75 dB at 1 kHz from any line input to any microphone channel and below 70 dB across 20 Hz to 20 kHz. The input impedance is greater than 1 kilohm, and the system provides more than 18 dB of headroom above the nominal +4 dBu output level.

Front-panel signal indicators make activity on all four input and four output channels visible. Network Sys and Sync indicators provide Dante operating feedback, while the Ethernet indicators show link and transmission-speed status. Together, these indicators allow essential audio, network, and power conditions to be checked directly at the interface.

What Makes It Different

This model handles both directions of conversion at the same time: four microphone or line sources enter the Dante network, and four Dante channels return as balanced analog line outputs. That arrangement consolidates network input and output functions without limiting the analog side to line-level sources. Selectable microphone operation, automatic gain, standards-based P48 phantom power, and the choice of PoE or 24 Vdc power give the RU-MLB4P flexibility for mixed analog and network-audio integration.

Final Assessment

The RDL RU-MLB4P provides a clearly defined 4×4 bridge between analog mic or line equipment and Dante audio. Its 24-bit conversion, selectable 44.1 or 48 kHz sample rates, balanced terminal-block connections, four +4 dBu outputs, automatic microphone gain, P48 phantom power, detailed status indicators, and IEEE 802.3af PoE support make it a capable choice for installations requiring compact, bidirectional Dante connectivity.