How do I get balanced audio out of a standard XLR mic?

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MattL2

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Joined 2014
#1
I have this standard microphone:
http://www.amazon.com/gp/product/B0002KZAKS/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

I use it to pull audio into my camcorder and my laptop, which can only be done by adapting the XLR plug into a common 1/8th inch jack. I accomplish this by using this balanced XLR-to-1/4" adapter:

http://www.amazon.com/gp/product/B000068O4C/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

Which plugs into a 10 ft stereo cable that adapts 1/4 inch to 1/8 inch. This:

Amazon.com: Hosa Cable CMS110 1/8 inch TRS to 1/4 Inch TRS Adapter Cable - 10 Foot: Musical Instruments

So here's the problem. Both the left and right channels coming out are identical. This results in phased silence when it's plugged into my laptop (because the DAC I use converts stereo inputs to mono), and audible unbalanced stereo when using my camcorder, which just sounds weird. Obviously neither are desirable. I want the L and R channels balanced so I get clean mono. The Hosa adapter says it's balanced, so why do I get unbalanced audio? More importantly, what can I buy instead that will give me the result I want? I would really appreciate links to Amazon or similar sites for a 10 ft XLR-to-1/8th" cable, or a proper adapter to replace mine. Thanks!
 
#2
your taking the opposite ends of a single phase feed from a microphone and wondering why your getting squat when you sum them to mono?(if only i had a nickel for every time i gotta teach a noob 'bout balanced lines shessh!)
i can point you to a few primer texts on mic's and balanced lines...
but in fact your solution can be easily assembled with a small handi box a couple of jacks and few bits of wire...
 
#4
MattL2 said:
You don't have to be condescending.
I'm really not looking to do any soldering and whatnot. Just looking for a simple $10 solution somewhere.
Click to expand...

Could you back up and explain what you are trying to do? I honestly cannot understand your 1st post in entirety. The answer to the question you posed about why the signal is unbalanced is that the cable you are using is unbalanced. However, the rest of your post sounds like you are trying to use the single microphone as a stereo source (L and R); is that correct?

EDIT: OK I read your post again and the mic spec again and it seems the silence you are getting is because you need a mic preamp to get the signal to line level. The whole balanced/unbalanced thing is a red herring.
 
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#5
No, preamp has nothing to do with it. It's just a phase cancellation. It's not that it's getting minimal sound, just none. I'm not trying to do anything with stereo, but my camcorder records in stereo, and the 3.5mm input is stereo. It won't record in mono. So I need to output a balanced signal where that one channel is 180deg from the other, that way I won't get awkward sounding doubled audio, Having opposite signals will also solve the laptop problem, as the DAC will convert them into a mono signal that doesn't cancel itself out.

So are you telling me that the cable is the problem is the cable? But the cable has two isolated separate channels, so I don't see how that makes sence.
 
#8
MattL2 said:
No, preamp has nothing to do with it. It's just a phase cancellation. It's not that it's getting minimal sound, just none. I'm not trying to do anything with stereo, but my camcorder records in stereo, and the 3.5mm input is stereo. It won't record in mono. So I need to output a balanced signal where that one channel is 180deg from the other, that way I won't get awkward sounding doubled audio, Having opposite signals will also solve the laptop problem, as the DAC will convert them into a mono signal that doesn't cancel itself out.

So are you telling me that the cable is the problem is the cable? But the cable has two isolated separate channels, so I don't see how that makes sence.
Click to expand...

You are somehow conflating a balanced signal with 2 channels. They are not even close to being the same thing. Your theory about perfect phase cancellation resulting in no sound at all is silly. Read up about it yourself if you don`t want to listen to advice.
 
#12
You appear to be running into the problem that TRS plugs/sockets can be used for two quite different purposes:
1. stereo unbalanced connections
2. mono balanced connections
If you try to do both at the same time then you are likely to get 'stereo' with a phase inversion between channels, so summing to mono gives nothing.

You need to convert your balanced mike to an unbalanced mono signal (i.e. just TS, not TRS), then split it into two unbalanced stereo signals.
 
#13
i truly apologize i did not intend to be condescending as this is a diy forum most are looking to create or assemble solutions to problems.
in order for you to find a ready made solution with off the shelf parts i think you need to develop a better understanding of what your interconnecting and how it functions and why so when your store bought solution doesn't work you'll have a better idea why.

note to self : not everybody wants my help
 
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#17
as long as the "balanced" pre has two unbalanced outputs that are in the same"phase" so he can fed his "two" inputs(which is where the problem starts) i probably should have suggested... no wait that involves making connections which the OP was not interested in so i'll shut up now.
 
#20
xlr's should be described as NORMAL PHASE (hot)pin2,REVERSED PHASE 180 DEG(COLD)pin3 and GROUND pin1.
i probably should follow my own advise and shut up but i can't.
the OP was taking the opposite ends of a single mic transformer and summing them to mono and wondering why his output was non existent! if i'm the only one that see's this as a problem i really need to re-evaluate the 25+ years i've been dealing with microphones and balanced lines and the like.

i think my wife's right ...i have a masochistic streak a mile wide

apologies in advance for spelling, punctuation,and sentence structure
 
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