balanced output

[joel]

I know balanced audio outputs are better than unbalanced outs but I'm not sure why does anyone have a good place to do more research or a quick answer? Are balanced aud. outs always XLR or can they be RCA as well?

 

[jaxvon]

Balanced outputs are always XLR because there need to be 3 conductors. The two signal conductors run in a twisted pair, 1 cable carrying the exact opposite of the other. This approach cancels out crosstalk as well as increases immunity to noise and reduces noise output. The third conductor is the shield to ground. An RCA output could not be balanced because it only has two conductors: center pin and shield (ground). Balanced outputs are useful when you have to run a long distance with your signal. They are much more immune to noise than RCA type unbalanced cables. RCA cables aren't really meant to be much more than 1-2m because of their inability to keep noise out at long lengths (in the audio frequencies).

 

[Richard Black]

RCA connections can often run tens of metres with no detectable noise problems. And while it's true that balanced connection is inherently a better system, in a lot of equipment (domestic and pro) there is extra circuitry to convert internal unbalanced operation to balanced output, and vice versa at inputs, and if that circuitry ain't just perfect you'll probably do more harm than good going balanced.

 

[invstbiker]

XLR to RCA

OK, I have a question along the same lines...I have a pre-amp with both balanced XLR outs AND RCA outs. My Amp has only the RCA connectors. Do I need to bother with a stepped approach XLR-RCA or just use the RCA's. My componants are less than 2 feet apart. Is there any advantage to the former?

THX

 

[markw]

No. don't bother with the XLR connectors.

OK, I have a question along the same lines...I have a pre-amp with both balanced XLR outs AND RCA outs. My Amp has only the RCA connectors. Do I need to bother with a stepped approach XLR-RCA or just use the RCA's. My componants are less than 2 feet apart. Is there any advantage to the former?

THX

but, after what the other posters tokle you, if it's gonna keep you up nights worrying, then feel free to go that route.

 

[invstbiker]

Thx Mark, Yes I just used the RCA's, sounds fine, I'm not going to worry about balanced.

Steve

 

[Privateer]

in a lot of equipment (domestic and pro) there is extra circuitry to convert internal unbalanced operation to balanced output, and vice versa at inputs, and if that circuitry ain't just perfect you'll probably do more harm than good going balanced.

Or like some of the Mcintosh equipment the entire product is balanced through out.

 

[timwill]

Hi dudes newbie here.

To expand on what jaxvon wrote:

There are a few advantages in using balanced lines. The most important is that the two signal wires (hot & cool) carry the same signal, but in anti-phase. When, at the destination of the cable the signal is converted to unbalanced, the cool is phase inverted (so it is in phase with and added to the hot). Any interference picked up along the balanced line - from mains, dimmer switches, etc. - is also phase inverted. The result is that the interference is on the cool cancels the interference on the hot!.

IMHO there is no need to go the balanced route if you are running short cables, especially at line level (which is what preamps output at). If you are getting interference over a few meters at line level, then you should look for the source of the interference.

 

[Francious70]

http://www.sounddomain.com/ride/321753/9

A pretty good explanation of balanced transmission.

 

[BMXTRIX]

Just as an added note: Balanced audio does not always have to be carried on XLR connectors, as that is just a connection type. It DOES require three conductors though. So, it can't be done with an RCA type connection which only supports two conductors. Most pro gear, that is professionally wired in place, actually uses phoenix type connectors. It may go to a wall XLR connector, microphone, etc.

So, while the most common interface consumers actually see and use it the XLR type because it is easy to connect/disconnect and is fairly durable, the 3 wire into a phoenix connector is the most common that commercial installers deal with.

Like this - XLR on one end, phoenix on the other: