balanced and unbalanced

what's this all about? what's the purpose of having something balanced or unbalanced. i use TRS cables and i noticed that the Y cable connected to my turntable amp (stereo) is balanced from the single end but not from the two ends that go into my MPC's record ins. the TRS cables i use from my MPC to my studio monitors also are unbalanced.

what would be the difference if i used balanced cables? would it minimize extra noises like a hiss or any kind of interference coming from some outside source?

From this site: http://www.undergroundfiles.com/recunder2.html

1. Balanced Vs Unbalanced

Doesn't that title sound like some kind of surreal WWF bout? "And in this corner, wearing black thongs and a leather gimp suit, Unbalanced!!"... Hehe. Seriously, though, we are talking about audio cables. There is constant reference to balanced vs. unbalanced cables and it took a long time before I actually understood what the difference was. In simplest of terms, unbalanced cables are your everyday mono instrument cables. Just so that you know, all RCA cables are unbalanced. Only 1/4" cables come in the balanced or unbalanced variety (and in this discussion I am referring only to 1/4" cables). For identification purposes, you can always tell when a cable is unbalanced as it only has one black ring on the jack. Balanced cables have two black rings. Some people call them stereo cables, which is misleading because they're used for much more than just stereo signals. But, in fairness, all stereo cables are balanced-- they have two black rings. By the way, the rings are not always black-- that's just how I'm referring to them, O.K.? So no e-mails correcting me or I'll burn your house down!!!

So, what's the difference? Well, first of all, balanced cables are ground compensated whereas unbalanced ones aren't . This results in cleaner signals which are hotter and have less noise. Some of you may have noticed reference to +4 versus -10 jack levels in your owner's manuals. Balanced jacks are always +4. Unbalanced are -10. It is wise to match jack levels with proper cables. So, if the jacks on your board or instrument are +4, you should use balanced cables. If they are -10, you may use unbalanced. What you shouldn't do is use unbalanced cables when balanced ones are called for. That is, you may use balanced cables on unbalanced, -10 jacks without any sound degradation but you should try to avoid using unbalanced cables on balanced jacks.

Is there a sonic difference? You'd better believe it! Balanced cables are more efficient and lead to cleaner, quieter signals. Recently, we were experiencing alot of noise coming off of our E-mu e-6400 sampler, especially SCSI noise that was finding it's way into the audio path. We switched out all of the unbalanced cables with balanced ones and the difference was unbelievable. Not only did we get rid of the SCSI noise, we also noted significantly hotter and quieter signals coming to the board which means we don't have to push the preamps as much. And, we've noticed greater hi-end resolution of all samples as a result. So it's no lie when you read that better, balanced cables make a difference. They really do. The down side is that balanced cables are not cheap. They are about double the cost of normal, unbalanced mono cables which adds up pretty quickly. But the difference in sound quality is well worth it. Since switching out the E-mu, one of our main goals is to switch our entire system to balanced.

One final note on this subject. XLR cables (microphone cables) are always +4, balanced. So, when buying a piece of gear, if the inputs or outputs are balanced, either 1/4" or XLR, you know you are getting a better piece of gear in terms of the signal it can handle. If the gear has only unbalanced 1/4" or RCA jacks, it is aimed more at the consumer rather than professional market.

Hi - I would not be too focused on the cable part of balanced audio connections as this does not really explain what is going on. All the clever stuff is to do with the fact that sending equipment sends your signal twice, signal A and signal B (an inverted version of A). The receiver receives:

Signal A + noise
Signal B + noise (remember, B is just A inverted)

The really clever bit now happens. When the receiver re-inverts signal B all the non-original audio (the noise) is totally removed.

To visualise this: if you get the same audio signal and add random noise to two copies, by subtracting A from B all you are left with is the noise as A and B will totally cancel each other out (the noise can then be subtracted leaving just the original signal)

So, the leads are important but these are just the carrier. Without the clever stuff happening inside your balanced synths/mixers/etc there is no gain.

Here is a cool little site: http://www.mediacollege.com/audio/balan ... anced.html

see you,

digi thats good info. i want to go totally stereo. everything stereo. so i guess that means switching out all my cables. which would be a good thing. kinda like spring cleaning i guess. but thanks for the info it helped. hey, so to make everything stereo i would need all balanced cables right? its that easy? because since i started this hardware game i've been trying to figure out how to get stereo sound....

Is there really an advantage in using balanced cables on unbalanced sources and destinations? you just get two ground wires.

"Is there really an advantage in using balanced cables on unbalanced sources and destinations? you just get two ground wires."

I dont believe so and in some cases you can introduce ground loops (hum). I think the ground loop issue may occur if you have a balanced output plugged into a non-balanced input using a balanced cable. The 'spare' connection can sometimes produce a ground loop.

One thing to always remember about balanced signals is that it is a mono technology. A balanced lead looks like a stereo lead but it can only carry a mono balanced signal (you need 3 wires for a mono balanced signal; you would need 6 for stereo).

that just confused the shi* outta me.

thanks, digi and punk, good info. i still have a question though. i'm looking at my 2000xl's manual and it says the stereo outs are unbalanced. my monitors accept both balanced and unbalanced jacks. should i stick with the unbalanced cables i have to avoid any ground loops or would it be okay to switch? even if i were to switch, it doesn't seem like it'd make any difference in the quality because of the unbalanced outs. ??

Hi Qwerty. Unfortunately your example is one that I am not sure. However, I am fairly certain that using balanced leads in such a setup will not give any advantages but may actually cause hum (ground loops). The easy solution is to stick to unbalanced leads. If you try balanced leads, just carefully listen for any introduced hums.

see you,