Running audio source 150 ft to distributed audio source

[bclancy]

What kind of cable would work best in the following situation.

I am running a signal from either a dj or live band from the line out of a mixing board, 100-150 feet into the amplifier that powers the house speakers...

I would like to use RCA jacks at both ends. Can I use coax or do I need something else.

 

[highfigh]

You don't run high impedance audio over long distances. It loses a lot of amplitude and picks up a lot of noise. You need to run it from a low impedance balanced output to a low impedance balanced input. High Z is for short local runs only and LowZ is specifically for noise rejection and long runs. If the amp(s) only have RCA inputs, I would recommend getting different amps. Also, the chance of having a ground loop is much greater if you run the audio over an unbalanced cable.

 

[TLS Guy]

You don't run high impedance audio over long distances. It loses a lot of amplitude and picks up a lot of noise. You need to run it from a low impedance balanced output to a low impedance balanced input. High Z is for short local runs only and LowZ is specifically for noise rejection and long runs. If the amp(s) only have RCA inputs, I would recommend getting different amps. Also, the chance of having a ground loop is much greater if you run the audio over an unbalanced cable.

I agree completely, for that sort of distance a 600 ohm balanced line is mandatory. If you use a high impedance unbalanced RCA terminated line, you will regret it.

 

[WaynePflughaupt]

C'mon guys, we're talking about a live-sound PA here, and using low-end equipment to boot!

Clancy, I had a gig once where due to an equipment failure I had to run unbalanced audio at least that distance between the mixer and the amps on the stage. It worked fine. Just keep in mind that with an unbalanced signal, your cable - or rather how well you cable is shielded - will make or break you, as far as pickinig up noise is concerned. Coax is about as good as it gets as far as shielding goes because it has both a foil and braided shield. I'd go with RG-6 and use F-to-RCA adaptors.

Regards,
Wayne A. Pflughaupt

 

[highfigh]

C'mon guys, we're talking about a live-sound PA here, and using low-end equipment to boot!

Clancy, I had a gig once where due to an equipment failure I had to run unbalanced audio at least that distance between the mixer and the amps on the stage. It worked fine. Just keep in mind that with an unbalanced signal, your cable - or rather how well you cable is shielded - will make or break you, as far as pickinig up noise is concerned. Coax is about as good as it gets as far as shielding goes because it has both a foil and braided shield. I'd go with RG-6 and use F-to-RCA adaptors.

Regards,
Wayne A. Pflughaupt

Your case worked by coincidence. Low end equipment running low Z is exactly why I recommended NOT using unbalanced runs. The chance of a ground loop is very high when the company cut corners to hit a price point and using ground loop isolators won't necessarily be the best way to deal with it. Also, good shielding won't matter if the grounding is bad.

 

[Rickster71]

This is exactly the situation balanced XLR's are made for.

 

[highfigh]

This is exactly the situation balanced XLR's are made for.

But it's more that the cabling and input/output is balanced and low impedance and that's the reason for my comments, although I didn't specify XLR plugs.