Behringer 73 Microphone Line Preamplifier 500 Series Module

Behringer 73 is a 500 series microphone and line preamplifier designed for professional recording and audio production environments. It enables microphone and line signal amplification for engineers and studio workflows, supporting recording chains where precise gain control and transformer-based amplification are required. This makes it ideal for 500 series rack systems used in studio tracking, mixing, and broadcast applications.

The module operates as a Class A discrete preamplifier with transformer-balanced input and output stages. It integrates stepped gain control, trim adjustment, and switchable input configurations for compatibility with microphone and line sources.

In practical use, it can be installed in standard 500 series racks to provide front-end signal amplification for microphones and instruments. Its switching and gain architecture supports studio recording, voice capture, and instrument tracking workflows.

Key Features

• 500 Series Microphone Preamplifier: Compact preamp module designed for standard 500 series racks
• Class A Signal Path: Fully discrete Class A circuit architecture for signal amplification
• Midas Transformers: Custom-built transformer-balanced input and output stages
• Stepped Gain Control: Electronically controlled resistor-stepped rotary gain switch with up to eighty decibels of gain
• Versatile Input Handling: Supports microphone and line input sources with selectable gain ranges
• Integrated Trim Control: Output trim control with phantom power switch integration
• Signal Monitoring: Signal indicator LED and phantom power status indication
• Front and Rear Input Selection: Switchable front or rear input routing for flexible rack integration
• Illuminated Control Switches: Phase, impedance selection, and input selection switches with illumination
• Transformer Balanced I O: Balanced signal connections through transformer-coupled circuitry

Technical Specifications

Audio Inputs
Microphone
Type: XLR and 1/4 inch TRS combi socket, transformer balanced front
Connection to 500 series rack input connector, transformer balanced rear
Impedance: 1200 Ω / 300 Ω, balanced
Max input level: +10 dBu
Sensitivity: -20 dB to -80 dB in 5 dB steps
Mic EIN @ 80 dB gain, 22 Hz to 22 kHz: -125 dBu unweighted

Line
Type: XLR and 1/4 inch TRS combi socket, transformer balanced front
Connection to 500 series rack input connector, transformer balanced rear
Impedance: > 4 kΩ, balanced
Max input level: +28 dBu
Sensitivity: -20 dB to +10 dB in 5 dB steps
Noise at unity gain, 22 Hz to 22 kHz: -83 dBu unweighted

Audio Outputs
Type: Connection to 500 series rack output connector, transformer balanced rear
Impedance: < 100 Ω balanced
Max output level: +28 dBu with 100 kΩ load, +26 dBu with 600 Ω load

System Specifications
Frequency response: 20 Hz to 20 kHz, ±0.5 dB
Distortion (THD+N): <0.07%, 50 Hz to 20 kHz, +4 dBu
Noise: -83 dB, 22 Hz to 22 kHz unweighted

Controls
Buttons: Phase/Polarity reverse
Lo Z: 1200 Ω / 300 Ω, operates on the mic input only
FR / R: Switches between the 500 series rack input and front combi connectors

Controls
Rotary sensitivity switch: +10 to -80 dB in 5 dB steps
Trim control: -20 dB to +5 dB with unity gain center detent
+48 V phantom power: Press trim control knob to enable or disable
Off = < -25 dBu, Green = > -25 dBu, Red = > +26 dBu

Power Requirements
Voltage: +16 V, -16 V and +48 V
Power consumption: +16 V ≤ 200 mA, -16 V ≤ 15 mA

Physical
Standard operating temperature range: 5 °C to 45 °C (41 °F to 113 °F)
Dimensions (H x W x D): 132.1 x 37.9 x 176.4 mm
(5.2 x 1.5 x 6.9")

Weight
1.1 kg (2.4 lbs)