Five-channel Automatic Mixer

  • Four automatic Mic/Line inputs, plus Aux in
  • Automatic threshold setting
  • 48V phantom power individually selectable for each channel
  • Limiters on each mic channel prevent individual channel overload
  • Balanced inputs and output, selectable Mic/Line-level
  • Individual gain controls for each channel
  • Switchable manual mode overrides automatic functions
  • Master output level control
  • Pre- or post-controller audio outputs from Mic/Line channels
  • Off attenuation for each input adjustable to -40 dB
  • Sub-D connector for TTL output, plus closure-control input for external control of each channel
  • NOMA operation provided, can be turned on/off
  • Output level meter with Peak and RMS modes
  • Monitor headphone output with adjustable level
  • Internal AC supply
  • Mounts in a single 19" rack space
  • Includes rack mount adapters

    The AT-MX351a automatic mixer is ideal for meetings, seminars, teleconferencing, worship services, courtroom proceedings, radio and TV broadcasting and A/V applications.
    All switching is under microprocessor control with proprietary algorithms for instant, seamless operation. An individual priority pre-select switch for each mic/line channel allows choice of one-channel-at-a-time operation, all active, or any mix of moderator override.
    The last microphone on stays on so that ambient sound is never muted. Plus, any number of SmartMixers can be linked to create a system for large multi-mic installations. The priority control system extends throughout the entire chain.

  • AT-MX351a Specifications

    Input Impedance

    Mic: 8,000 ohms / Line: 50,000 ohms / Aux: 50,000 ohms / Link In: 20,000 ohms

    Output Impedance

    Balanced: Line--200 ohms, Mic--300 ohms / Unbalanced: 400 ohms / Link Out: 100 ohms / Preamp Out: 750 ohms

    Maximum Input Level

    Mic: -24 dBV Line: +27 dBV Aux: +17 dBV

    Maximum Output Level

    +22 dBm

    Nominal Output Level

    Balanced Line: +4 dBm (600 ohms), +4.4 dBV (open circuit) Mic: -46 dBm (600 ohms), -44 dBV (open circuit) Unbalanced: -10 dBV (open circuit) Preamp Out: -10 dBV (open circuit)

    Headphone Output

    700 mW, 20 ohm load

    Maximum Gain

    73 dB

    Frequency Response

    40 ~ 22,000 Hz

    Equivalent Input Noise

    -128 dBV (150 ohms) at maximum gain

    Input Attenuation

    10 dB

    Mic/Line Input Pads

    50 dB

    Maximum NOMA Attenuation

    ≈20 dB (up to 100 mics on simultaneously)

    Phantom Power

    +48V DC

    Control Voltage Out

    +4V DC

    Power Supply

    100V-240V AC, 50-60 Hz, 30W

    Operating Temperature Range

    32°F to 104°F


    3.35 kg


    430.0mm X 238.0mm X 44.0mm (L X W X H)

    Accessories (Optional)

    AC power cable; AT8325/1.0 Link Cable; rack mount adapters; security caps


    audio technica support AT-MX351a_OME.pdf - Operation Manual (English)
    audio technica support AT-MX351a_OMC.pdf - Operation Manual (Chinese)