xlr vs unballanced

No. AFAIK a balanced cable works better over longer distances, offers a bit more volume level and supports ground lift switching.
 
yek said:
. . . offers a bit more volume level . . .
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Funny, everyone writes that. I haven't noticed a higher level when I changed from unbal. to bal. outs. Should I be worried or is it just a barely noticeable difference?
 
Maybe not noticeable difference at home/studio, but in a live situation where the output and the FOH are 20,30,40... meters away, yes ;)
 
Over short distances there should not be any noticeable difference between the two.
Over distances, like going 100'+ to FOH, XLR's (properly wired low impedance w/ ground) work much better. They do this by sending the SAME signal down both wires - using a common ground - but out of phase with each other.
When the receiving end receives the signal it recombines "the out of phase" legs, thereby dramatically reducing signal loss.
This does not occur in the standard 1/4" TRS cable.
 
The xlr outs of my Ultra are definitely hotter than the unbalanced outs. That's all I use now. But I also believe as the others, it's focus is for lower "noise level" of the signal
 
To the SLA-2 it does not so mind.
The real point to me is giving the sound guy the XLR's, so you can travel your signal to all the noise source on stage and get it to the mixer clean from noise.
 
Balanced audio uses common mode rejection. This is one of my favorite things ever invented because it's clever and very useful.

Basically you take the signal and invert it 180 degrees out of phase. You send the original and the phase shifted signal to your destination. Along the way your signal is going to pick up RF interference on both of these signals. The destination equipment will take the two signals and send them through a differentiator which amplifies the differences of the two signals and cancels out the similar portions. Well the only part of the 'signal' that is in phase is going to be the RF noise. The output of the differentiator is the original signal minus the noise.

It frickin rocks. :mrgreen:

Unbalanced audio on the other hand is just a ground a the signal. Any RF that is picked up along the transmission path is embedded in the signal and the destination has no way to determine what was the original audio and what is noise. You usually end up having to filter it out by frequency which works, but you also end up losing that part of the original signal.

For short runs with minimal RF it's fine most of the time. I'd never use it in an actual studio though.

The only thing that you have to look out for with balanced audio is ground loops (actually you have to worry in both cases, but unbalanced has no practical solution). Anyway that is when the chassis ground between two devices is at different potentials or one has a shorter distance to ground. Electricity flows to the path of least resistance and the last thing you want is that voltage difference running through your audio path. It can create a nasty hum, heat components and be dangerous for the equipment as well as people using it.

So you use the ground lift at the source or just don't connect it if the device doesn't have a switch.

The ground is made at the destination since the noise isn't present right at the output and will be picked up as it travels (that's how I remember it anyway). By breaking the ground connection at the source you eliminate potential ground loops and this is common practice in every studio I've ever worked in.

Balanced audio also uses a reference of +4dBm in most cases. Unbalanced audio is considerably lower (I can't remember, but -10dBm seems to stick in my mind). A 14dB difference is considerable. You won't hear that since the equipment is aligned for unity gain, but it gives you a much higher signal to noise ratio for the cable.
 
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