Shure Microflex M300 Series User manual

MX392 MX393
Boundary Microphones
The Shure small, surface-mounted electret condenser microphone series, MX392-393, user guide.
Version: 4 (2019-J)

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Table of Contents
MX392 MX393Boundary Microphones 3
General Description 3
Features 3
Model Variations 3
Interchangeable Cartridges 3
Permanent Installation 5
MX392 and MX393 5
Microphone Placement 6
MX392BE 6
Configuration 8
DIP Switches 8
Wiring Diagram 8
Mute Button Configuration 9
Connecting to an Automatic Mixer 10
Logic Wiring 10
Changing SWITCH OUT to Always Momentary 11
Painting 11
Specifications 12
Furnished Accessories 15
Certifications 15

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MX392 MX393
Boundary Microphones
General Description
Shure Microflex MX300 Series microphones are surface-mounted electret condenser microphones designed primarily for
mounting on conference tables, stage floors, and lecterns. Their high sensitivity and wide frequency range make them espe
cially suitable for picking up speech and vocals in sound reinforcement and recording applications. Interchangeable cartridges
provide the installer with greater flexibility and make it possible to easily reconfigure microphone coverage as the need arises.
The MX392 and MX393 models include an internal preamplifier.
MX300 Series microphones take advantage of the principle that, at a barrier or boundary, the sound pressure level doubles.
When placed near a sufficiently large boundary surface, the microphone has 6 dB higher sensitivity and approximately 3 dB
greater direct-to-reverberant sound ratio.
Features
The MX392, MX392BE, and MX393 feature programmable logic input and output. Additionally they provide following benefits:
Flat frequency response across the vocal range for uncolored sound
Interchangeable cartridges that provide a choice of polar pattern for each application
Sleek, low-profile design for surface mounting
Programmable mute button
LED indicator
Logic input/output for remote control or use with automatic mixers
RF filtering
Model Variations
The polar pattern of the included cartridge is indicated by a model number suffix:
/C Cardioid
/S Supercardioid
/O Omnidirectional
/N Cartridge not included
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Interchangeable Cartridges
Microflex microphones use interchangeable cartridges that allow you to choose the polar pattern for different installations.

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Cartridge Polar Patterns
Permanent Installation
MX392 and MX393
Remove grille to access mounting key holes.
Cut slots into pads.
Slide microphone forward to engage screws in slots.

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Note: If using rear side-exit cable option, only drill two outer holes.
Microphone Placement
For best low-frequency response and rejection of background noise, place the microphone on a large, flat surface, such as a
floor, table, or lectern.
To reduce reverberance, avoid reflective surfaces above or to the side of the microphone, such as beveled sides of pulpits or
overhanging shelves.
MX392BE
Once placement has been determined, the microphones can be permanently installed. First, drill the hole in the selected area
to allow the bottom entry cable to be conveniently routed out of sight. Then use the pressure sensitive adhesive to keep the mi
crophone firmly in place.
Drilling the hole:
Determine the cutting area for the bottom exit cable and drill a 1/2" (12.7 mm) circular hole. Remove all debris from the
mounting surface.
Route the cable through the drilled hole.
Connect the cable to a mixer or P.A. system.

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Pressure Sensitive Adhesive
Thoroughly clean the application area with the included alcohol wipe. Removing the dust will allow the microphone to
adhere well.
Remove the adhesive backing and gently set the microphone into position.
Once the microphone is in position, firmly apply pressure to the microphone.
Note: The pressure sensitive adhesive will be extremely difficult to move once pressure has been applied.
Bottom view of MX392BE/C with adhesive pads
Re-Routing Cable for Bottom Exit (If your MX392 is not BE configured)
Remove the grille.
Disconnect wires from screw terminals.
Grasp rubber boot within 1/2" of housing, using gas pliers. Rotate boot and cable ccw to remove connector from thread
ed "L" bracket.

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Remove cable from microphone housing.
Insert cable through access hole in microphone base.
Insert cable connector through hole and thread it into "L" bracket.
If desired, rubber strain relief can be reattached to cable end or removed from cable before fastening it to bracket.
Re-connect wires to proper screw terminals on circuit board.
Insert supplied round rubber plug into unused side cable exit.
Reinstall grille and foam screen.
Insert cable through hole in mounting surface. Secure microphone to mounting surface.
Configuration
DIP Switches
Use the DIP switches to configure logic settings and mute button behavior.
The DIP switches are covered with a piece of clear tape at the factory. Remove tape to modify the switch settings.
OFF (factory default) ON
1Momentary Toggle
2Push-to-mute Push-to-talk
3Mute button enabled, LED illuminates when mic is active Disable mute button (microphone always on), logic controls
LED
4-- --
Wiring Diagram
NOTE: Audio and logic ground are connected at microphone base.

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Mute Button Configuration
Use DIP switches 1 and 2 to configure the mute button, as follows.
Be sure to set DIP switch 3 off (factory default) so that the mute button controls audio from the microphone.
Switch Function DIP Switch Setting
Momentary: push-to-mute (as shipped).
Momentary: push-to-talk
Toggle: (Push On/Push Off): Mic is active when powered on

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Switch Function DIP Switch Setting
Toggle: (Push On/Push Off): Mic is mute when powered on
Connecting to an Automatic Mixer
Use these settings if connecting the microphone to an automatic mixer or other device that mutes audio and controls the LED.
Connect logic leads to the automatic mixer. Connect the LED IN to the gate output to illuminate the LED when that
channel is gated on.
Set DIP switch 3 on. This disbles the mute button (the microphone passes audio regardless of whether the button is
pressed or not).
Set DIP switch 1 to configure how the mute button sends SWITCH OUT logic:
Momentary: push = 0 Vdc, release = 5 Vdc
Toggle: initial = 5 Vdc, push = 0 Vdc
Logic Wiring
Green (LOGIC GROUND): Connects to the logic ground of an automatic mixer, switcher, or other equipment.

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Orange (LED IN): Set DIP switch 3 on to use LED IN. When shorted to LOGIC GROUND, the LED turns on.
White (SWITCH OUT): Provides TTL logic (0 Vdc or 5 Vdc) in response to the mute button. Set DIP switch 1 for momentary or
toggle. When phantom power is applied, logic initializes high (5 Vdc). DIP switch 2 has no effect on SWITCH OUT.
Changing SWITCH OUT to Always Momentary
Use the following modification in situations where your logic interface requires momentary closure of the SWITCH OUT, but
you want the mute button to toggle the microphone (DIP switch 1 ON, 3 OFF):
Access the circuit board inside the microphone base.
Remove the resistor at R45 and reinstall it at location R46.
Painting
Asupplied plastic paint shield
Bretainer
Cgrille
Dfoam screen
Esupplied adhesive masking strip
Fsupplied rubber plug

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Remove foam screen from grille before painting
Clean surfaces to be painted with denatured alcohol or naphtha.
To avoid filling grille holes, apply paint in thin layers.
Important: Use fine sandpaper to remove paint from the bottom edges of the grille. This ensures electrical continuity
for proper shielding.
Specifications
All measurements taken with microphone mounted on a wooden surface (76 x 76 cm)
Type
Electret Condenser
Frequency Response
50–17000 Hz
Polar Pattern
MX392/C, MX392BE/C, MX393/C Cardioid
MX392/S, MX392BE/S, MX393/S Supercardioid
MX392/O, MX392BE/O, MX393/O Omnidirectional

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Output Impedance
180 Ω
Output Configuration
Active Balanced
Sensitivity
@ 1 kHz, open circuit voltage
Cardioid –30 dBV/Pa
Supercardioid –28 dBV/Pa
Omnidirectional –22 dBV/Pa
1 Pa=94 dB SPL
Maximum SPL
1 kHz at 1% THD, 1 kΩ load
Cardioid 119 dB
Supercardioid 118 dB
Omnidirectional 111 dB
Self Noise
A-weighted
Cardioid 23 dB SPL
Supercardioid 21 dB SPL
Omnidirectional 15 dB SPL
Signal-to-Noise Ratio
Ref. 94 dB SPL at 1 kHz
Cardioid 71 dB
Supercardioid 73 dB
Omnidirectional 80 dB
Dynamic Range
1 kΩ load, @ 1 kHz
96 dB
Common Mode Rejection
10 Hz to 100 kHz
45 dB, minimum
Clipping Level
at 1% THD
–6 dBV (0.5 V)

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Polarity
Positive sound pressure on diaphragm produces positive voltage on pin 2 relative to pin 3 of output XLR
connector
Mute Switch
50–20000 Hz
–50 dB minimum
Logic Connections
LED IN Active low (≤1.0V), TTL compatible. Absolute maximum voltage: 0.7V to 50V.
LOGIC-
OUT
Active low (≤0.5V), sinks up to 20mA, TTL compatible. Absolute maximum voltage: 0.7V to 24V (up to 50V
through 3kΩ).
Cable
MX392 3½ m (12 ft) attached cable with shielded audio pair and three conductors for logic control, unterminated
MX392BE 3½ m (12 ft) attached cable with shielded audio pair and three conductors for logic control, unterminated, bot
tom exit
MX393 3½ m (12 ft) detachable cable with 3-pin audio connector
Weight
172 g (0.38 lbs)
Environmental Conditions
Operating Temperature -18-57 °C(0-135 °F)
Storage Temperature -29-74 °C(-20-165 °F)
Relative Humidity 0-95%
Power Requirements
11-52V DC , 2.0 mA

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Furnished Accessories
Paint Mask 80C514
Switch Paint Mask 80A541
Set of 5 rubber pads with adhesive RPM470
Certifications
Meets essential requirements of all applicable European Directives.

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Eligible for CE marking.
The CE Declaration of Conformity can be obtained from Shure Incorporated or any of its European representatives. For contact
information please visit www.shure.com
The CE Declaration of Conformity can be obtained from: www.shure.com/europe/compliance
Authorized European representative:
Shure Europe GmbH
Headquarters Europe, Middle East & Africa
Department: EMEA Approval
Jakob-Dieffenbacher-Str. 12
75031 Eppingen, Germany
Phone: [phone]
Fax: [phone]
Email: [email protected]