XLR cable for unbalanced connection

[jarthel]

XLR has 3 conductors. and the 3 wires/connectors are usually +/- signal and ground.

I was thinking of something like:

+ = right channel
- = left
ground = ground

instead of 2 male-terminated RCA cables going from preamp to poweramp, I only have one.

good idea? or bad idea?

 

[Geek]

Hi,

Crosstalk will kill your channel seperation.

 

[Hartono]

bad.......

 

[jarthel]

and I had such high hopes for it!

thank you very much

 

[Keruskerfuerst]

You need to use one cable per cannel and ground one wire at one side.

 

[jarthel]

wouldn't there be any crosstalk on an xlr cable? or maybe there's none because the +/- signals cancels this?

 

[richie00boy]

Once wired for 2 channels the balanced feature is lost, so there is not +/- cancelling.

There will not be a big crosstalk issue if good cable is used and the length is not too long.

Remember Naim use almost the same scheme. It has the advantage of preventing ground differences between channels.

My only change to your proposal would be to use the + as left and the - as right. It just follows convention better that way.

 

[jarthel]

wouldn't there be any crosstalk on an xlr cable? or maybe there's none because the +/- signals cancels this?

I was unclear and I apologise for that.

I meant crosstalk on a xlr cable used as an xlr cable (1 channel per cable and not left/right channels on the same cable).

 

[AndrewT]

Hi,
what if one used two twisted pairs feeding the stereo XLR?
One pair for left and one pair for right.
The ground connection meeting in the plug and taken into the audio ground attached to the socket.

How would crosstalk measure with this arrangement?

Would this increase or decrease the propensity for hum?

 

[richie00boy]

Both crosstalk and hum would be reduced However, the propensity to get ground voltage differences would be similar (but a bit better) to using normal phono connections.

 

[AndrewT]

Hi,
the closeness of the two pairs would reject some of the external hum field. The common audio ground connection may also help reduce loops in some wiring arrangements.
If the PCB audio/signal ground is taken to the XLR socket and from the socket to main audio ground then this is likely to be as quiet as as any other grounding arrangement and better than most.

The send end of the cable would require a 4pole or 5pole XLR and complete separation of the two channel audio grounds in the source.