Audio cable signal splitting

jack63ss

Member
WHAT is the correct way to split the signal from a wireless mic receiver so I can run it to 2 different amps ?

So the situation is this. I have a choral group of 50-100 for which I mic a piano that is in the pit in front of them with a speaker on the stage behind their risers. I currently use an old NADY wireless mic set and an old Pyne guitar amp/speaker, and it works reasonable well. My problem is they, picky people that they are, would like 2 speakers instead of just 1 in the center. So I bought 2 guitar practice amp/speakers (10amp), primarily because they were inexpensive and small. All 3 amp/speakers have a 1/4" input and an 1/4" output and individually work fine with the mic. Now the problem.
I though I could just string input-output-input, but turns out all 3 outputs are headphone, so they cut out when I plug a cable in. So we decided to just SPLIT the cable from the mic. Nope, got all kinds of noise. Which leads to my question. WHAT is the correct way to split the signal from a wireless mic receiver so I can run it to 2 different amps ? I am sure there is a way to do it, I just can't figure it out.

Thanks
Jack
ps I'm a lighting guy doing double duty, so please cut me as much slack as possible. :)
 

Amiers

Renting to Corporate One Fixture at a Time.
A console. Mic in to speaker outs.

Also a lighting guy no slack given 😜
 

microstar

Well-Known Member
One good approach might be to use an "audio distribution amplifier "(ADA) but it would likely cost more than your guitar amps.
But since you are laser-focused on cheap, you could get something like the Galaxy Audio JIBS which takes one input and has 4 outputs; you will only use 3 of the outputs in your scenario.
You MUST use 1/4" to 1/4" phone plug SHIELDED cables to connect everything. Do not use speaker cables (which are not shielded) or you will have massive hummm problems.

JIBS-Top-Front-Angled.jpg
 

FMEng

Well-Known Member
Fight Leukemia
With all due respect to the other responders, neither of those will address the root cause of the hum and buzz. Guitar amps are notorious for picking up noise, even when used for their intended purpose, due to the high input impedance and being unbalanced (1 conductor plus shield). Add in a couple of different AC grounds and long audio cables, and you have the perfect recipe for ground loop hum galor.

Without having any more equipment specifics, let me recommend the following:

Use the following transformer at the input of each guitar amp
https://www.sweetwater.com/store/detail/A85F--shure-a85f-line-matching-transformer

Assuming the Nady receiver has an XLR output, use a Hosa Y cable
https://www.sweetwater.com/store/detail/YXM121--hosa-yxm-121-y-cable-xlr3f-to-dual-xlr3m-6-inch

Both of those items are widely available. Then, use XLR F to XLR M cables to make the runs from the receiver to the guitar amps. For added insurance, use a ground lifter at the amp farthest from from the receiver.
https://www.sweetwater.com/store/search.php?s=hosa+ground+lift

The transformers and XLR cables make the interconnections balanced (2 conductor plus shield), which the proper way to do it.
 
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TimMc

Well-Known Member
Premium Member
Return the f'n guitar amps. Get your money back.

Buy or rent a pair JBL Eon 10s or 12s. Or any number of similar products from QSC, Alto (bargains, they usually are), RCF, Yamaha. If your wireless mic does not have a balanced XLR output, get a transformer as FM suggests, then go to the first Eon (or equal) and out of its loop to the other Eon.
 

Ben Stiegler

Well-Known Member
and much as I love the founder of Nady, who donates his mansion annually to a non-profit jazz group fundraiser I work with, its pretty likely that your Nady is in a now-prohibited freq band. Why are you messing with wireless at all? A wired XLR output mic on the piano is 100x more reliable. And ... putting the piano monitors behind the chorus is also suboptimal. look at how your ears are shaped. The pinnae (ok, pinnas) are evolved to catch sound from the front and sides - and reject the rear. You can run those speakers/amps at much lower level, with better high frequency transmission by placing them in front of the choral risers and tilting them up. If you are micing the choir, put the speakers directly behind your mics so they live in the cardiod rejection node of the mic.

Have fun - poke me if questions [email protected]
 

MNicolai

Well-Known Member
Premium Member
Fight Leukemia
Yeah....as others have said, you should not be using guitar amps for stage monitors. Guitar amps are purpose-built for a specific instrument. They are not intended to be stage monitors for other types of instruments or vocals, nor are they intended to be quiet in terms of hum/background noise. They are also not a flat, ideal representation of the signal coming into them. Guitar amps are actually built specifically to colorize the signal going into them, which is absolutely not what you want for a stage monitor application.

If you must use guitar amps, go with what @FMEng posted. That's the best way to isolate some of the noise. The ideal solution is to get actual stage monitors. For what you're doing, I prefer QSC K8's or K10's, or the equivalent models from EV, but you can certainly get by with less.
 

StradivariusBone

Custom Title
Fight Leukemia
Behringer makes decent powered multipurpose speakers if you're on a budget. I've used a couple of their models in school settings with success. Many of them will also give you an actual line output that you can then daisy chain them together from a single line source. The only time I've used a guitar amp as a monitor is for an actual guitar and we miked the amp for signal and pointed it at the guitarist so he could hear himself.
 

BCAP

Well-Known Member
When you absolutely have to split microphone or line signals and have no other choice to achieve the result, Radial Engineering makes a number of excellent microphone splitters and line level audio splitters. These devices usually have transformers in them, they are designed to do the job and they have ground lifts on them which is also a big help.

Some wireless mic receivers have 2 outputs and the ability to deliver either or both a line level output or a microphone level output. Such as certain Sennheiser or Shure series. I have in the past used simultaneously the XLR balanced out for PA system application and 1/4" out of a receiver for recording application. It can work well.

However as others have said in this thread there are a number of different, maybe better ways to fundamentally set up your rig. I agree with many of the other comments on the thread. If it were me trying to solve the issue you describe I would use a wired mic or mics on the piano (or possibly a piano pickup, if it's decent) into a small mixer board, send an aux from the mixer out to powered monitor speakers with line inputs and outputs and you could daisy chain them. That would be one way.

I walk into theater environments where people are using guitar amps as monitors, I understand it's an inexpensive and quick way to do things but I almost always replace them with monitors I provide, I use QSC K12 and K12.2. This way I can run balanced line cables to the monitors from the returns and the monitors are designed for more of a full frequency range.
 

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