Mic / Line Distribution Amplifier

The RDL RU-MLD4T is a mic/line distribution amplifier that takes a single input and provides four outputs. Its front panel supplies XLR input and output jacks, while detachable terminal blocks on the rear provide another connection format. A rear-panel switch selects mic or line operation for the input, and every output can also be switched between mic and line level. Selectable mic gain, selectable phantom power, and an adjustable front-panel input gain trim provide control at the source.

Ideal Use Cases

This model fits systems that need to distribute one microphone- or line-level source to four output paths. It accommodates workflows that benefit from front-panel XLR access as well as installations wired through rear detachable terminal blocks. Because input mode and each output level are switch-selectable, the RU-MLD4T is suited to configurations in which the source and connected destinations do not all use the same nominal signal level.

• Distributing a single mic signal to as many as four mic- or line-level destinations.
• Distributing a line source while setting outputs individually to mic or line.
• Systems requiring front XLR access or rear terminal-block connections.

Why Choose This Model

The core advantage is level flexibility throughout the signal path. The input is not fixed to one signal type, and the four outputs are not locked to a common mic/line setting. The unit also supports two selectable mic gain ranges, labeled LO GAIN and HI GAIN, plus switch-selectable phantom. Front-panel gain trim allows the input gain to be adjusted without moving that control to the rear. This combination concentrates input selection, mic setup, gain adjustment, and four-way distribution in one model.

Installation and Integration

Connection can be made from the front using XLR jacks or from the rear using detachable terminal blocks for both the input and all four outputs. Input mic/line selection and output mic/line selection are located on the rear panel. Set the input mode for the incoming source, choose LO GAIN or HI GAIN when using the mic input as required by the specified level range, select phantom as needed, and set each output for the level expected by its destination. The front-panel trim then provides final input gain adjustment.

Power requires a ground-referenced 24 Vdc source rated for 90 mA. The recommended supply is the PS-24AS for the USA or PS-24AX for international use, and the power supply is not included. The specified ambient operating environment is 0° C to 55° C. Package dimensions are 6 x 6 x 2.625 inches, with a shipping weight of 2.375 pounds.

Performance Highlights

For a +4 dBu output, the listed mic input levels are 48 dBu to -3 dBu in LO GAIN and -65 dBu to -20 dBu in HI GAIN; the listed line input range is 15 dBu to +28 dBu. Output impedance is 150 Ω balanced. THD+N is specified at less than 0.1% in mic operation and less than 0.005% in line operation. CMRR is greater than 60 dB for mic and greater than 50 dB for line. Line-output headroom is greater than 20 dB above a +4 dBu output.

What Makes It Different

The RU-MLD4T combines dual connector access with per-output level selection. Front XLR jacks support direct access, while rear detachable blocks accommodate a separate connection approach. More importantly, each of the four outputs can be set for mic or line rather than relying on a single output-level choice for the entire group. The input section adds its own mic/line switch, selectable mic gain and phantom, and gain trim, distinguishing the model through configuration at both the input and output stages.

Final Assessment

The RU-MLD4T is a focused choice when the requirement is one switch-selectable mic/line input, four independently selectable mic/line outputs, front XLR connectivity, and rear detachable terminal-block connectivity. Its published performance figures cover distortion, common-mode rejection, headroom, and balanced output impedance, while the front gain trim and rear selections keep setup controls clearly divided. Confirm the required 24 Vdc supply separately, because it is not included.