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Omnidirectional Condenser Boundary Microphone

U.S. Two-Year Limited End-User Warranty

*Manufacturer's Suggested Retail Price. Actual selling price may vary; please check with an authorized Audio-Technica dealer.

  • Overview
  • Features
  • Specifications
  • Downloads
  • Reviews
  • Q & A

  • Overview

    The U841A delivers exceptionally intelligible audio reproduction in a super-compact, low-profile design. Equipped with UniGuard® RFI-shielding technology, this omnidirectional condenser boundary microphone is designed for clear, highly intelligible sound reinforcement, professional recording, television and conferencing in surface-mount applications. The U841A has a 360° pickup angle and operates on battery or phantom power.
  • Features

    • Designed for surface-mount applications such as high-quality sound reinforcement, professional recording, television, conferencing and other demanding sound pickup situations

    • UniGuard® RFI-shielding technology offers outstanding rejection of radio frequency interference (RFI)

    • UniSteep® filter provides a steep low-frequency attenuation to improve sound pickup without affecting voice quality

    • Small-diameter UniPoint® capsule near boundary eliminates phase distortion and delivers clear, high-output performance

    • Heavy die-cast case and silicone foam bottom pad minimize coupling of surface vibration to the microphone

    • Low-profile design with low-reflectance black finish for minimum visibility

    • Operates on battery or phantom power

  • Specifications

    ELEMENTFixed-charge back plate permanently polarized condenser
    POLAR PATTERNOmnidirectional in hemisphere above mounting surface
    LOW FREQUENCY ROLL-OFF80 Hz, 18 dB/octave
    OPEN CIRCUIT SENSITIVITYPhantom: –39 dB (11.2 mV) re 1V at 1 Pa
    Battery: –40 dB (10.0 mV) re 1V at 1 Pa
    IMPEDANCEPhantom: 200 ohms
    Battery: 270 ohms
    MAXIMUM INPUT SOUND LEVELPhantom: 132 dB, 1 kHz at 1% T.H.D.
    Battery: 122 dB SPL, 1 kHz at 1% T.H.D.
    DYNAMIC RANGE (typical)Phantom: 111 dB, 1 kHz at Max SPL
    Battery: 101 dB, 1 kHz at Max SPL
    SIGNAL-TO-NOISE RATIO73 dB, 1 kHz at 1 Pa
    BATTERY CURRENT / LIFE0.4 mA / 1200 hours typical (alkaline)
    SWITCHOff, on-flat, on-roll-off
    WEIGHT (MICROPHONE)2.8 oz (78 g)
    WEIGHT (POWER MODULE)4.9 oz (139 g)
    DIMENSIONS (MICROPHONE)2.56" (65.0 mm) diameter,
    0.59" (15.1 mm) height
    DIMENSIONS (POWER MODULE)3.31" (84.0 mm) H x
    2.48" (63.0 mm) W x
    0.87" (22.0 mm) D
    CABLE25.0' (7.6 m) long (permanently attached to microphone), 0.13" (3.2 mm) diameter, 2-conductor, shielded cable with TA3F-type connector
    ACCESSORIES FURNISHEDAT8531 power module; battery; soft protective pouch
    Click on the chart to view the larger image

  • Downloads

    UniPoint Review - Sound & Video Contractor (pdf 128.21 KB)
    UniPoint Review - Pro Audio Review (pdf 238.70 KB)
    U841A Specification Sheet (pdf 302.60 KB)
    U841A Submittal Sheet (pdf 482.19 KB)
  • Reviews

  • Q & A

    I am seeing one of these used and advertised as "cardioid". My question is: Does the U841A come as a cardioid? I am under the impression from this website that it is omni-directional only. Please confirm.


    The U841A from us (the manufacturer) is sold with an omnidirectional capsule. The capsules are interchangeable and that particular dealer may have installed the cardioid capsule. It would not be recommended though as that is not the "actual product" at that point any may not be an authorized Audio-Technica Dealer. For information on changing the capsules, you may find helpful information here:


    Hello. I am seeing 2 product numbers: U841A and AT841UG. Are these the same product? Thank you


    No, the AT841UG is an older model.


    Does this microphone have a mute/unmute button?


    No. You may use the U891Rx or similar microphone with an inline local mute control.


    I'm a court reporter. I am using the DM246 which accepts XLR plugs. I hooked the AT841UG to it and I get nothing. What am I doing wrong? My system does support phantom mics. Any suggestions?


    Please contact our Audio Solutions Department at (330) 686-2600 ext 5000 or at for assistance with this.


    You say the U841A has a low-frequency cutoff filter. How, if at all, can one switch it off?


    The Low-Frequency cutoff filter is the on the AT8531 power module, which is necessary for use with the U841a. On the power module, there are three settings: off, bent-line, and straight-line. The straight-line means normal frequency response. The bent-line is the Roll-Off, and Off means that the microphone will not pass audio. If you have any further questions, please contact the Audio-Technica United States (ATUS) Audio Solutions Team at: Thanks!


    Is there a adapter/devise for this Microphone where it can be mounted it to the ceiling?


    Thank you for your inquiry. Please contact our Audio Solutions Department at (330) 686-2600 ext 5000 or at for assistance with this.


    Is the U841a sold as each or by the pair?




    Coverage Range of U841A hey Folks, as far as the specifications are concerned what is the estimated optimal coverage radius of the OMNIDIRECTIONAL CONDENSER BOUNDARY MICROPHONE U841A? Is it approved/recommended for a 15 foot radius? 25 foot radius? 5 foot radius? If you could provide its optimal coverage radius that would be great! Its intended use is in a video conferencing boardroom setting. Thanks!


    Thank you for your inquiry. As in all things audio the answer to your question is "it depends". It depends on how loud your sound source is verses how loud the background noise is. It depends on how high you can set the gain on your audio system. It depends upon whether the microphone is used for sound reinforcement within the room where it is used or if it is used in video / audio conference or in a recording. Also, very importantly it greatly depends upon the acoustics of the room. All of these factors is one reason it can be a good idea to use an audio consultant or sound contractor when setting up a room and buying equipment.


    Is there an alternative microphone for U841A with mic on and off button? I am using this microphone for Cisco C40 codec.


    Thank you for your inquiry. We have the U891RCx that has a switch, although it has a cardioid element. If you need an omni microphone, you can purchase the UE-O element speparately and replace the element in the mic.


    need to connect u841a to mixer desk We need to connect u841a to mixer desk, with xlr inputs: what do we need to do this?


    Thank you for your inquiry. You will need a standard XLRF to XLRM microphone cable. The power module has an XLR male connector. Please note if your mixer provides phantom power, the microphone will use it. If not it will use the on board batery.