Shure MX392/C Microflex Boundary Condenser Microphone Cardioid

Product Overview

The Shure MX392 is a Microflex surface-mount electret condenser boundary microphone designed for conference table, lectern, stage floor, and installed surface audio applications. Using the boundary effect principle, the MX392 achieves 6 dB higher sensitivity and approximately 3 dB greater direct-to-reverberant sound ratio compared to a conventional overhead microphone at equivalent distance. A programmable mute button with LED indicator, logic input/output for automatic mixer integration, and interchangeable cardioid, supercardioid, or omnidirectional cartridges make the MX392 the standard specification-grade boundary microphone for commercial conferencing, government, and installed AV environments. Available with cardioid (/C), supercardioid (/S), or omnidirectional (/O) cartridge.

Product Description

The MX392 features an internal preamplifier delivering active balanced output with 180 Ω impedance, a dynamic range of 96 dB, and self-noise of 23 dB SPL (cardioid) — specifications that satisfy commercial AV buyers specifying microphones for HVAC-affected boardrooms, government spaces, and training rooms with reverberant acoustic conditions. The programmable mute button can be configured via DIP switches for push-to-mute, push-to-talk, or toggle modes, and the logic wiring allows gating control from automatic mixers such as the Shure SCM820 or third-party DSP platforms. The RF filtering ensures reliable operation in facilities with dense wireless infrastructure. The low-profile sleek design can be surface-painted for installation in custom-color furniture or architectural surfaces. The attached 3.5 m (12 ft) cable is pre-wired with shielded audio pair and three logic conductors for direct connection to mixing consoles and automatic mixers.

For installations requiring a detachable cable, see the Shure MX393 Microflex boundary microphone at Creation Networks. For bottom-exit cable installations through furniture surfaces, see the Shure MX392BE bottom-exit variant.

Key Features

• Boundary Effect Design — Mounting on a large flat surface achieves 6 dB higher sensitivity and approximately 3 dB better direct-to-reverberant sound ratio compared to conventional overhead placement at equivalent source distance, improving speech intelligibility in reverberant rooms.
• Interchangeable Cartridges — Cardioid (/C), supercardioid (/S), and omnidirectional (/O) cartridges are field-swappable without tools, allowing polar pattern reconfiguration to adapt coverage as room layout or use changes.
• Programmable Mute Button with LED Indicator — DIP switch-configurable for push-to-mute, push-to-talk, or toggle modes; the LED provides active/muted status to talkers for professional conference room operation.
• Logic Input/Output for Automatic Mixer Integration — Logic wiring enables gate control from automatic mixing systems and DSP platforms for unified room audio management in conference and government AV installations.
• Active Balanced Output — 180 Ω active balanced output provides noise-rejection across long cable runs typical in installed AV systems with centralized rack equipment.
• 96 dB Dynamic Range — Handles the full dynamic range of speech and vocal applications in commercial spaces from quiet conference rooms to high-SPL all-hands environments.
• RF Filtering — Internal RF filtering provides reliable performance in facilities with dense wireless microphone, cellular, and IT infrastructure.
• Paintable Housing — Can be surface-painted for installations requiring color-matched microphones in custom-finish conference tables or architectural surfaces.
• Flat Frequency Response Across Vocal Range — 50 Hz to 17 kHz frequency response delivers uncolored speech and vocal capture for natural intelligibility in conferencing and reinforcement applications.

Typical Applications

• Conference room and boardroom table-mounted boundary microphone systems
• Government space and secure conference room audio capture
• Lectern and stage floor microphone placement for houses of worship and auditoriums
• Training room and all-hands room surface-mount boundary microphones
• Commercial meeting space audio installations with automatic mixer integration

Technical Specifications

Frequently Asked Questions

What is the difference between the MX392 cardioid, supercardioid, and omnidirectional variants?
The cardioid (/C) provides a heart-shaped pickup pattern that rejects sound from the rear, suited to rectangular conference tables with a defined talker zone. The supercardioid (/S) has a tighter front focus with some rear pickup, preferred in rooms with side noise sources. The omnidirectional (/O) picks up equally from all directions, best suited for round tables or meeting environments where talker position is variable. Cartridges are field-swappable without tools.

How does the MX392 connect to an automatic mixer?
The MX392 includes logic wiring (LED IN, SWITCH OUT, LOGIC GROUND) for integration with automatic mixers. Set DIP switch 3 to ON to disable the mute button and allow the automatic mixer to control the LED. The SWITCH OUT provides TTL logic (0/5V) for gate status reporting back to the control system.

Can the MX392 be used on a glass or reflective conference table?
Shure recommends placement on a large, flat surface for best low-frequency response and noise rejection. Reflective surfaces above or to the side of the microphone (such as glass or beveled furniture edges) can increase reverberance. For glass table surfaces, a foam isolator pad is recommended to reduce vibration coupling.

Can the MX392 housing be painted to match custom furniture?
Yes. The MX392 housing and cable can be surface-painted to match custom table finishes. Shure supplies a paint mask accessory to protect the microphone cartridge during painting. Use thin coats of paint to avoid filling the grille holes, and remove paint from the bottom edges of the grille for proper electrical shielding continuity.

What is the warranty on the MX392?
Shure products are backed by Shure's standard limited warranty. Contact Creation Networks or Shure support at shure.com for current warranty terms and RMA procedures for commercial AV installations.