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Not working with Mackie mixer

  • Hi there,

    I am trying to use the 3dio FS with an 8 channel Mackie mixer. I am using a stereo mini jack to 2 mono 1/4" jack splitter cable. When I plug these into the left/right on one channel of the mixer I get no signal. When I plug them into 2 channels I get a signal but stereo to both ears, no binaural effect. I also tried plugging the mono ends into a splitter to make it single stereo jack into the mixer, didn't work either.


    I also tried it with a Behringer micro mixer using the adapter to make it a single 1/4" stereo input, this worked but it was very hard to tell if there was any binaural effect - it felt like maybe there was a little, but not as much as you would expect.

    the battery is brand new.

    let me know what you think!



  • Audio Wizard
    Staff member

    Hi @Hannah White,

    Thank you for your question. I'm happy to help.

    I'm not sure what model of Mackie mixer you have, but these instructions should be universal.

    1) Turn the Phantom Power on the mixer to the OFF position.
    2) Plug the white tip 1/4" jack of the splitter cable into the line input (or combo XLR / 1/4" input) of channel 1.
    3) Plug the red tip 1/4" jack of the splitter cable into the line input (or combo XLR / 1/4" input) of channel 2.
    4) Plug the 3.5mm end of the splitter cable into the 3Dio and turn the power switch on the mic to the ON position.
    5) Pan channel 1 all the way to the left (fully counter-clockwise).
    6) Pan channel 2 all the way to the righ (fully clockwise).
    7) Set the gain/trim knob for both channels to exactly 12 o'clock.
    8) Set the faders for both channels to 0 or "U". (this is typically around 75% of maximum for sliding faders, 50% for knobs).
    9) Set the MAIN to about 50% and set the headphone output to about 50%.
    10) Plug headphones into the headphone output.

    This should give you a binaural signal where you can clearly hear the left and right ears separately.

    Let us know if this doesn't work and we can continue to troubleshoot.

    Thank you!

    3Dio Customer Care

  • Many thanks - that worked as far as the mixer is concerned. However there's another step in the chain - the mixer is then connected to an 8 channel 'listening centre', with 8 stereo headphone ports so 8 people can listen at the same time - I've tried connecting the listening centre via mono and stereo cables, via main out and headphone out, but neither work - they reduce the signal back down to a normal stereo signal.

    Also I'm assuming that the mini mixer won't work binaurally as there's no capacity to pan? 

    thank you!

  • Audio Wizard
    Staff member

    Hi @Hannah White,

    Thank you for the additional info.

    Just so I understand you correctly, you were able to verify a stereo binaural signal from the microphone into the mixing console? And you confirmed this by plugging headphones into the mixer's headphone output and confirmed that the ears are separated in the headphones left and right?

    If so, can you confirm that the cable you are running from the mixer to the "listening center" is a TRS cable? In other words, can it support an unbalanced stereo signal? Does the "Listening Center" support stereo audio? I was unable to find any info online about the Listening Center hub.

    Regarding the Behringer Micromix, that will not support a stereo signal. All the inputs and outputs on that device are mono.

    Thank you and looking forward to your reply.

    Best regards,

    3Dio Customer Care

  • Hiya - yes, i was getting a stereo binaural signal from the mic using the mackie mixer, and confimred this using the headphone port.

    then i tried running from the mixer to the listening centre using the attached cable - by TRS do you just mean stereo? as far as i can tell from googling that's what this means? sorry I'm not familiar with the TRS description.

    the 'listening centre' we were trying to use had a mono input so we tried resoldering a stereo input but this still didn't work. it is an old japanese unit so there is no info online! aesthetcially we like it so we're trying to get it to work :) we had already changed the headphone porst to stereo ports to get each one in stereo, which worked fine, but i'm guessing now it was receiving a mono signal via the port which it split to stereo in each headphone output.

    we then tried connecting the mixer to this brand new multi headphone unit:


    with the same cable - the one attached - but still just got a signal in one ear. any ideas?

    thank you!

  • Audio Wizard
    Staff member

    Hi @Hannah White,

    Yes, by TRS, I mean stereo. TRS stands for Tip, Ring, Sleeve. It is the same connector as an Aux cable for a car or home stereo.

    The Behringer microamp doesn't support stereo, so that wouldn't work.

    With the Listening Centre, my guess is that ALL of the wiring and all of the jacks would need to be replaced in order to convert to stereo. It sounds like you've replaced all the jacks though. Was the wiring also replaced to include both the left and right signals in addition to ground?

    Finally, if there is a circuit board inside the listening centre, then I would bypass that entirely and hardwire all the jacks, as the schematic most likely doesn't include a circuit for a 2nd signal (right) to be included.

    Is the Listening Centre passive? I don't see any power adapter or anything else plugged into it.

    Best regards,

    3Dio Customer Care

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