Equalizer for In Ear Monitors? (IEMs)

Discussion in 'Live Sound [BG]' started by StrangerBasses, Oct 1, 2017.

  1. StrangerBasses


    Oct 30, 2016
    Hey everyone,

    I have a quick question regarding EQ ear buds. Lately, I've been getting some (what I think is called RF interference) coming through my IEMs. It seems to be tied to stages that are lit with Neon lights, though I'm not sure. I've tried troubleshooting (changing frequencies, etc), but certain stages really seem to give me some bad, high pitched squeaks and shrills coming through my buds.

    I was wondering if there was an easy fix for this by using an equalizer of sorts for my ear buds on the receiving end (i.e., the sounds come post-board, so I have to cut the frequencies on my end). Has anyone ever done this? Perhaps used some sort of small, headphone EQ unit to cut high frequencies and such?

    Any help would be great with this problem, thanks!!
  2. Geri O

    Geri O Endorsing Artist, Mike Lull Guitars and Basses Gold Supporting Member

    Sep 6, 2013
    Florence, MS
    There is, but you will be much better served by addressing the source of the interference. Usually that interference is caused by mid-wired or broken fixtures and/or their power supplies. Also, bad or mis-wired DMX cables can cause interference problems, too.

    Good luck, and I hope you get that sorted out quickly.
    s0c9 and StrangerBasses like this.
  3. walterw

    walterw Supportive Fender Commercial User

    Feb 20, 2009
    what system is it? are you maybe on a now-illegal RF band? maybe the transmitter needs to be physically moved away from something else on stage, like other wireless stuff?
    i don't see how; even if the interference was a narrow single pitch and always at the same sonic frequency so you could notch it out with a parametric, you'd be putting a big hole in the actual sound too.

    i hope you have a limiter set up if these noises are coming through loud, that could be dangerous to your hearing.
    StrangerBasses likes this.
  4. StrangerBasses


    Oct 30, 2016
    Thanks for the help guys!

    So, I'm actually using the band transmitters and receivers (wireless system is the bands, buds are my own westone UM20s). I'll check the RF bands. They do have the transmitters all stacked into a rack-like system, which may be part of the problem. But, there are Five transmitters, but no one else seems to have this problem.

    Forgive my neivetty, but wouldn't a limiter only help if it was on my receiver (I.e., these sounds are being "caught" somewhere between the transmitter and receiver, so any pre-transmitter limiting/EQinng wouldnt help... correct?)

    Nonetheless, my last show I shut my IEMs completely off because I couldn't take the whizzing and shrilling aounds, so no problem with hearing loss. I usually keep my receiver levels wayyy down.l anyways... in this sense, I sort of use my receiver volume controls as a "limiter" in sense.

    Well I'll check a few things, thanks guys!!
  5. walterw

    walterw Supportive Fender Commercial User

    Feb 20, 2009
    yeah, you're right; if the interference is happening between the box and the pack, then limiting before the box wouldn't help.

    it would be down to any limiting in the pack itself, but it seems like most of the time unless that setting is adjustable then it doesn't seem to kick in until you're already too loud.
    all the same brand? you might just be stuck with a defective system, in which case there's no getting around it with other measures, it needs to be fixed.

    maybe the external antenna on the transmitter is loose or broken, or even just in need of being popped off and reattached a few times to clean off any oxidation at the BNC jack?

    for a while i was using a provided old shure PSM400, which started creating hideous crackling static noises whenever the transmitter was physically bumped, or often for no reason at all.

    i took it apart, couldn't find anything obviously broken, re-flowed a bunch of solder joints anyway, and generally tightened and cleaned it up before putting it back together and all was fixed! it could have been a bad grounding screw connection inside the unit or something.
    Last edited: Oct 1, 2017
    StrangerBasses likes this.
  6. StrangerBasses


    Oct 30, 2016
    Sounds similar to my issue. We thought maybe it was the antenna, so we installed a new one, but the noises continue... ehhh.

    Also, I saw there is a "squelch" function on some receivers? Maybe engaging this would help? I think we are using seinhauser if I remember correctly...

    Thanks for the help!!
  7. s0c9

    s0c9 Supporting Member

    Jan 9, 2014
    1964 Audio artist, Fractal Audio Beta Tester
    yes, it might help..
    Does the noise happen at ALL venues, some, or just one?
    Do you know which Senn model you are using and which frequency band ..
    PM'd you..
  8. musicman7722


    Feb 12, 2007
    Hampton NH
    Rule out your box by asking your sound people to swap boxes with another person. All you have to do is change the connection at the board. If you still exp. then you can rule out your transmitter and receiver.
    s0c9 likes this.
  9. kalle74


    Aug 27, 2004
    Trying to cure transmission problems with EQ would be like trying to help a rusting car by painting on the rusty bits. It'll cover the problem, but the problem will still be there. And it would have nasty side-effects as well...

    Look into your system. Swap receivers with someone (as mentioned above). Rule out possible causes systematically. Adjust. Re-adjust.

    Wireless is not easy, nor without it's problems. But done carefully, it can get pretty good.

    That said, LED's seem to cause a lot of problems with wireless systems... As would sub-par antennas (and their poor placement) and faulty antenna cabling.