what's the difference between XLR and 1/4" cable? Balanced & Unbalanced?

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billbone

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I noted in a past post that I inherited the position as singer, and an old PA. my next question -

What's the difference between the XLR jack and a 1/4" jack? I have a mic cable that has a detachable 1/4" jack adapter. Do I get lesser quality using that adapter?

Also - what is balanced and unbalanced with it comes to mics?
 
an XLR connector is round barrel usually with 3 pins (can be more in some cases)
a 1/4" connector is a larger version of the 1/8" connector you see in typical consumer headphones. There are two tyes of 1/4" connectors...TRS and TS.
TRS stands for Tip/Ring/Sleeve while TS is just Tip/Sleeve. A TRS connector has two small black rings around it separating part of the metal from the tip and the sleeve....while the TS type only has a single black ring around it.

These connectors are used with specific types of gear that accept them. All gear should tell you what type thye use.
XLR and TRS connectors are used with balanced gear. Balancing the audio is a 'trick' to help reduce extra noise that is picked up in the cables in the form of Electromagnetic Interference and Radio Frequency Interference. This trick uses the principle of phase/polarity and how two exact opposite signals react with each other when put back together.
Unbalanced just means the signal going down the cable can pick up EMI/RFI if you're not careful. Usually these types of gear use TS cables.

There's lots of info on this site about this topic.
Don't call an XLR cable a mic cable...because it's not necessarily a mic cable until you hook it up to a mic. It can also be a speaker cable, a mixer cable, etc. Don't let that confuse you.
You need to understand what gear you have and what the intended way you are supposed to hook them up is. This can vary from equipment to equipment and is dependent on the output and input signal each item gives off.
 
bennychico11 is perfectly right above, One thing to add, is that an XLR = TRS for most intents and purposes. If you have the two bands on a 1/4 plug, you have a balanced cable, the shape of the jack doesn't make it different than a xlr "mic" cable other than that mics generally have a XLR plug system.

An XLR to 1/4 "adaptor" if it only has one band at the plug, is not the same though. people often yuse these to try to convert a mic level signal into a line level input (like a guitar amp), but the impedance is all wrong and it will sound like crap. Check this out: https://homerecording.com/impedance.html

Daav
 
with all this being said, today's test/observation probably makes sense:

I attached a TS 1/4" adapter to my mic's XLR plug, and plugged it into my PA. Sure enough, the volume dropped a bit more than when I plugged the XLR directly in!

So the solution here would be to go buy a TSR adapter for my XLR plug. The volume should be better. Right?
 
billbone said:
with all this being said, today's test/observation probably makes sense:

I attached a TS 1/4" adapter to my mic's XLR plug, and plugged it into my PA. Sure enough, the volume dropped a bit more than when I plugged the XLR directly in!

So the solution here would be to go buy a TSR adapter for my XLR plug. The volume should be better. Right?
Click to expand...

not necessarily. I think daav confused you with that post by Harvey. And although I understand what Harvey is saying, I don't think the multiple balanced-->unbalanced conversions are nearly something to worry about as much as multiple A/D/A conversions are.
Like I said, you need to know what you're plugging into what.
What kind of microphone are you using? Where are you plugging it into on the mixer? Remember, this is electricity we're talking about and you have to put electricity into it's appropriate places.
Probably what is happening in your case is the microphone is a Lo-Z (low impedance) microphone and it HAS to plug into the XLR. The reason being is microphones put off a very low voltage signal that has to be amplified. And in a mixer, after the XLR points, is a preamplifier that amplifies this low level signal up to line level. If you were putting the adapter on the XLR and then plugging it into the 1/4" input on the mixer...then you are bypassing the preamp and in effect telling the mixer that it's a line level device...which it's not.
A good general rule of thumb...mics get plugged into microphone inputs (ie. XLR inputs)
Line level devices like a tape player, outboard gear, and sometimes guitars get plugged into the 1/4" inputs.

The microphone was built with an XLR output on it for a reason. Match that XLR with an XLR input.

Now if your microphone states on it that it's a HI-Z microphone, that's another case...but let us know what microphone you're using first and what mixer.
 
my mic is a sm-57.
my mixer is an old junky Peavey XR 600E.

The reason I'm bothering with a 1/4" adapter is because the mixer's built in reverb is broken, and it's effects loop is completely worthless. I want to do something that is kind of ghetto (but it's cheaper and I can swing it):

I want reverb on my voice. I want to get a reverb pedal, plug my mic (with a 1/4" adapter) into it, then into the mixer.

By the way - for what it's worth, my TS XLR to 1/4" adapter does say "lo-z balanced" on it, which I didn't notice before. So my theory is out the window. I'm getting kinda confused, I really don't know then why there was a drop in volume (and probably tone). Subtle drop, but a drop nonetheless.
 
also confused a little here, too -
you said, "XLR and TRS connectors are used with balanced gear."
since this little adapter is only a TS, how come it says it's balanced?

have I tripped myself into the "Lost Zone"...? I don't mean to sound so dumb...
 
The SM57 is a low-Z microphone that needs to be plugged into the XLR inputs of your mixer. Period.
The reason the adapter says Lo-Z balanced on it is to tell you that it's not converting the signal to Hi-Z and that it is indeed a TRS connector. Or at least it should be a TRS connector. An example when you might use that adapter with an XLR cable is if you are plugging out of a mixer that has XLR outputs and going into a pair of active speakers that have 1/4" inputs. The signal stays the same, the connectors are just different.
Remember, these connectors and cables you are using do not denote what kind of signal you are using...generally speaking in your case. They are just there to give you options of how to plug your gear in. It's up to YOU to decide where the appropriate places to plug them into are.

Next, you said:
I want reverb on my voice. I want to get a reverb pedal, plug my mic (with a 1/4" adapter) into it, then into the mixer.
Click to expand...

a guitar reverb pedal has a Hi-Z input. The output of guitar jack is Hi-Z and has to be plugged into something that is Hi-Z. Your microphone is Lo-Z and low voltage and shouldn't be plugged into an effect pedal. You would need to boost the microphone signal up and then convert it to Hi-Z input. Then the output of the effect unit will be Hi-Z so then you need to convert again to Lo-Z if you're plugging it into a mixer that doesn't have Hi-Z....kinda confusing huh? That's why they make dedicated effect units for line level gear. BUT remember, always amplify a microphone signal with a preamp before doing anything with it.

also, are you sure the connector unbalanced then? Look at the picture below...does it have two back rings around it like that one?
And don't worry about being confused...a lot of people don't understand this, and this is the newbie section so you're alright. :)
 

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bennychico11 said:
The reason the adapter says Lo-Z balanced on it is to tell you that it's not converting the signal to Hi-Z and that it is indeed a TRS connector. Or at least it should be a TRS connector
Click to expand...

well, it only has one black band. I'm thoroughly confused now, because upon closer inspection of this adapter (with the Radio Shack logo on it), it says "Lo-Z balanced" on one side, and "Hi-Z Unbalanced" on the other side. In between those two labels is a schematic drawing I don't really understand. I have NO IDEA what this label is trying to tell me. The bottom line is, it has one black band.

I followed what you said about my reverb situation. Do you know any affordable device that can give me reverb for my mic WITHOUT using effects loops (since the effects loop on my old PA head is faulty)? Something that would take a XLR in, and pass through an XLR out?

I do have a Presonus TubePre that might be something that can help. It has a balanced (XLR) and an unbalanced (1/4) out. I don't know about it's Hi-Z or Lo-Z.
 
billbone said:
well, it only has one black band. I'm thoroughly confused now, because upon closer inspection of this adapter (with the Radio Shack logo on it), it says "Lo-Z balanced" on one side, and "Hi-Z Unbalanced" on the other side. In between those two labels is a schematic drawing I don't really understand. I have NO IDEA what this label is trying to tell me. The bottom line is, it has one black band.

I followed what you said about my reverb situation. Do you know any affordable device that can give me reverb for my mic WITHOUT using effects loops (since the effects loop on my old PA head is faulty)? Something that would take a XLR in, and pass through an XLR out?

I do have a Presonus TubePre that might be something that can help. It has a balanced (XLR) and an unbalanced (1/4) out. I don't know about it's Hi-Z or Lo-Z.
Click to expand...

Aha! Things are becoming more clearer....it helps when you clarify what gear you are talking about and what is written on them. Otherwise we're just taking a shot in the dark ;)

First, the adpater...this adpater is an impedance transformer. It is made to take a balanced signal that is lo-impedance (ie. a microphone) and convert it into an unbalanced hi-impedance signal (kinda like what a guitar's signal is). A reason this might be done is so you can plug your microphone into a guitar amp. Or perhaps plug it into a PA mixer that might only have Hi-Z inputs on it (as far as I can tell, yours has only Lo-Z inputs). Again, this is something called impedance matching. However, you don't need it. You can just plug your microphone directly into the mixer.

BUT you want to use reverb. Since you do have this adapter, I take back what I said earlier and you could actually use the effect pedal in the equation...however you're still going to have to convert it back to Lo-Z. This is not at all an ideal situation for many reasons and I recommend against doing it. However, since you mentioned you have a TubePre, I do recommend doing it this way:

Since your effects return is broken...
Plug the microphone into the tube pre via XLR (ignore that 1/4" adapter you have)
Get an effects processor/reverb unit like this or this
Run 1/4" out of the TubePre into the effects unit
Run 1/4" output (balanced or unbalanced...whatever it says for you to do) into your mixer's 1/4" input.
Bam! You got signal.

Here's more info on impedance and what it does to your signal.
http://whirlwindusa.com/tech03.html
 
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man, you are amazing. you were so much help. I read a ton of stuff elsewhere, but you are the only to make it clear. I hope you get credited for the great help you give -
thank you thank you thank you.
when you write your first instructional book on this stuff, please let me know. I'll buy.

It's really cool that you spent all this time on my little problem. Thank you.
 
my pleasure
keep reading and posting on this site and you'll learn a ton more. there are a lot of knowledgeable people here, so have fun!

-B
 
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