Balanced / Unbalanced.......

[Frankie]

So, I got this question for you pros.
I got balanced cabels from my speakers to the amp. And balanced from the amp to my mixer, but then I realized that my mixer's
balanced output is XLR and not jack...,so for now I'm using the unbalanced output. Does this make a lot of difference??? What is the difference of balanced/unbalanced anyway??

Frankie

 

[Guest]

Yo Frankie:

I'm not a PRO either; however, it seems that the balanced plugs, the three-prong dealies, give better results, especially when using a mic for a vocal; I can't give you the technical reasons but I've seen the answer on this forum given by Ed or SN##.

The 1/4 inch jack plugs are kind of universal; they are used for many, many ins/outs and are known as unbalanced plugs.

I get good results from both types; if you check out this forum and the right places, you will get your "technical" answer for sure.

Green Hornet

 

[T.J.Hooker]

Boy! Bob sure is right about better results. I know when I hook up a mic balanced it's much clearer and more powerful without the volume having to be cranked up. Anytime I can go Balanced I do. And I will until I have a problem with it. Then I'll come to this forum and ask one these recording God's, " WHAT THE F*@# DID I DO!" Good Luck Man!, T.

 

[sonusman]

First of all, I have never seen a speaker that required a Balanced cable. A speaker has a Hot (+) and Negative (-) connection. Speaker wire and audio wire are two totally different things, and should never be used for the other. Buy thick speaker wire for amp to speaker connections.

As to running balanced vs. unbalanced from the mixer to the amp, this is for more objective. If the distance from your mixer to your amp is less then about 20 feet, it will make little difference, IF, you do not have RFI interference going on in your studio.

Unbalanced cables are 2 conductor, a Hot (+) and a Ground. The ground is wrapped around the Hot lead and acts as a shield too.

Balanced cables are 3 conductor, a Hot (+), a Cold (-), and a Ground. Again, the ground is wrapped around the Hot and Cold leads and acts as a shield.

Where you may run into problems is with operating levels. In either a balanced or unbalanced connection, the operating level MAY be either -10 or +4. This is different then balanced and unbalanced, but there are certain "standard" practices in this.

Usually without fail these days, a Balanced connection will have a +4 operating level for the audio.

Unbalanced can go either way.

Now you have to deal with the issue of connector types. There are 1/4" unbalanced (a regular guitar cable, or a TS cable which means Tip Sleeve) and 1/4" balanced (what is called a TRS connection which stands for Tip Ring Sleeve). A 1/4" TRS connector is the same thing used for headphone connectors. It accomedates 3 wires. A TS connector only can take 2 wires.

On some devices like mixers, the 1/4" output connectors may be TS, or TRS. That is something you have to check. My Behringer compressors have balanced XLR and balanced 1/4" TRS on them. The 1/4" connectors can also be used for TS also, but this requires me to change the operating level of the device which is done with a little switch on the back.

If you need to get a XLR output to a TRS input, you can simply buy a cable with the appropriate connectors on either end, or buy an adaptor for either end that converts it to what you need.

Once again though, you should be more concerned with operating level. +4 is much better to use, and is consistent with all Pro audio gear. Also, balanced vs. unbalanced MAY be an issue depending upon how long the wire needs to be, or if you are getting interference from radio stations when you use unbalanced cable of any length.

Ed

 

[gaffa]

As usual, Ed is right, as well as being first with the answer, but I thought I might add a little bit myself.

Ignoring the numbers, the reason a balanced line is better, and the reason it is called a balanced line in the first place is simple, and once you understand it, pretty obvious.

There are three bits of wire in a balanced line - common, hot and cold.

Basically, the hot carries the signal, the common is the return path, and the cold effectively does nothing, except for....

In a long run of cable, interference is picked up. Simply put, the same interference is picked up on both the hot and cold lines (Ok, it's not "identical", but close enough).

The device that is receiving the signal performs what is known a "phase-shifting". It takes the signal from the hot line, which now carries the signal as well as the interference, and the signal from the cold line, which is just interference, shifts the phase 180 degrees, and combines the two signals together. This phase shift cancels out what ever signal was common to both wires, namely the interference. So the end result is that you have a signal in which the interference has been cancelled out.

Voila!

So it has effectively 'balanced' the two signals together, and thus is called a balanced line.

If you want a visual picture, draw a sine wave, then draw another sine wave over the top of it, but draw it so that whenever there is a peak in the first sine wave, the second sine wave is in a trough, and vice versa. THat's phase shifting. By adding the two waves together, you get 0

eg. image the that sine wave 1 peaks at +10, so sine wave 2 would be -10 and the same point (sine1 is at a high, while sine2 is at a trough)

-10 + 10 = 0

so it all cancels out.

See, all very easy, and I only used 2 numbers.

Remember, this doesn't contradict was Ed said, just expands on it. . Hope it helped a little

- gaffa

 

[Frankie]

Ok I see. I just changed from jacks to XLR
and tried the balanced output, and it sounds better (at least that's what I like to think.. ) I use really short cables so I quess it's not a big deal anyway. Thanks for helping me sorting it out!!

Frankie