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UniMix® 2-to-1 Microphone Combiner with Balance Control

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 AT8681 combines the output from two microphones into one channel. The balance control attenuates each microphone by 6 dB (typical) at midpoint.
  • Features

    • Professional XLR-type input/output connectors

    • Can be installed anywhere in-line, either at the mixer input or near the microphone

    • 24-48V DC phantom power and balanced cables required for operation

    • Permits phantom voltage to pass on to the microphone

    • Rugged steel housing

  • Specifications

    Input/Output Connectors XLRF/XLRM-type
    Phantom Power 24-48V DC, 2-4 mA typical
    Frequency Response 20-20,000 Hz
    Gain Unity (0 dB), +0/-1.5 dB
    Noise (A-Weighted) -115 dBV typical
    Weight 8.8 oz (250 g) typical
    Dimensions 5.12" (130.0 mm) W x
    2.36" (60.0 mm) D x
    1.73" (44.0 mm) H typical
    Input Impedance 10,000 ohms
    Output Impedance 250 ohms
    Maximum Input Level +15 dBV (1% T.H.D. at 1 kHz)
    Maximum Attenuation 33 dB at 1 kHz
    Notes UniMix specifications measured at 48V phantom power, 150 ohms input load and 100,000 ohms output load.

  • Downloads

    AT8681, AT8684 Specification Sheet (pdf 67.22 KB)
    AT8681 Submittal Sheet (pdf 135.53 KB)
  • Reviews

  • Q & A

    I want to run four microphones to hear the congregation in church. Can I run them through three of these combiners to bring them into a single input on the mixer?


    Thank you for your inquiry. Yes, but if using condenser microphones make sure that you do not draw too much current.


    Is there a version of this with ground lifts on the inputs? Also, do you make a version with terminal ins and outs?


    No we do not.


    Can this be used to connect two dynamic microphones to one channel of a mixer/amplifier that has no phantom power?


    Thank you for your inquiry. You may connect dynamic microphones to the UniMix, but it is designed to operate using phantom power.


    If I am understanding this correctly, if I am using two condenser microphones which need 48 volt phantom power, all I would need would be a single channal phantom power source? So the two condensor microphones would plug into the AT8681 and the 48V Phantom power source would go on the output and then into the mixer? Would this supply enough phantom power to the mixer for each microphone? Or would my life be easier just getting a dual Source phantom power box and running to Tom microphones off the AT8681?


    Thank you for your inquiry. This will work, although you may need to be concerned about the current draw of both mics. Most of the time this is not a problem.


    Is there any chance the mic pre providing phantom (such as an API 512 in a lunchbox) can be damaged due to the fact it is trying to provide phantom to 2 separate mics?


    No, the preamp will not be damaged but depending on the specifications of the microphones you are connected, the phantom power from your preamp is split between the two (plus a few volts for the AT8681 electronics.)


    Is it safe to use dynamic microphones with this device?




    Is it safe to use cardioid microphones with this product (since it uses phantom power)?


    Yes, you may use condenser microphones with the AT8681 as it passes phantom power.


    We're using two identical condensor mics at our pulpit, requiring two channels/two cables. Will this effectively combine the two signals to one channel, eliminating additional cabling, etc.?


    Yes, you may use the AT8681 for your situation. Additional information may be found here:


    If one input is connected to a mic with an on/off switch, and that switch is moved to the 'off' position, will the volume of the second mic jump?


    It will not make the volume jump, the channels are separate.


    Want to combine line level Stereo outs on a church organ and feed to mixing board. It does not like to have the channels combined and causes distortion. Are the inputs isolated and can the unit accept line level signals?


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