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RCA Patch cord question

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Old Nov 8, 2011 | 12:18 PM
  #1  
slip's Avatar
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RCA Patch cord question

I read the debates and I have a question. If the head unit puts out only .5 volts and travels around 16 feet to the amp, how can a better (smaller guage) patch cable not improve SQ?
on certain notes I get a small amount of "static" like noise but only on some songs and was just wondering what the opinions are for better cables

any opinions welcome, as I don't know much about SQ upgrades etc.

thanks
Old Nov 8, 2011 | 12:42 PM
  #2  
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Please explain how a smaller cable is ever better for transfering any voltage level, keeping in mind we are dealing with frequencies below 25,000hz?

The main ways that a cable can degrade the signal is through resistance, capacitance, and inductance. One would really have to do some crazy things to a wire to get a measurable capacitance or inductance issue and resistance is a problem only in the thinnest wire.
Old Nov 8, 2011 | 06:10 PM
  #3  
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Originally Posted by Dukk
Please explain how a smaller cable is ever better for transfering any voltage level, keeping in mind we are dealing with frequencies below 25,000hz?

The main ways that a cable can degrade the signal is through resistance, capacitance, and inductance. One would really have to do some crazy things to a wire to get a measurable capacitance or inductance issue and resistance is a problem only in the thinnest wire.
I think I should have said small gauge number, not smaller cable

so you are saying if the patch cord (example) has 22 gauge diameter wires and I went to say 12 gauge wire it would not make a difference in the quality of the signal (if the shielding is as good)
thanks for the help in trying to understand

randy
Old Nov 9, 2011 | 01:50 PM
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Ah yes, see I thought you were promoting that a smaller conductor (larger gauge#) was superior.

There are few to no drawbacks of a larger diameter conductor other than cost. I don't see any real point going larger than 16ga though. I use whatever primary wire I have available, generally 16-18ga.
Old Nov 9, 2011 | 06:34 PM
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the gauge of rca wire for such low level signals is really insignificant. There is very little current being carried. 12 gauge for RCA wire is kind of laughable! Sorry to say.

For the math: the output resistance of a preamp is very low, maybe 10 ohms or less. The input resistance of an amp is maybe 10K to 100Kohm. both numbers give or take 10% anyway. So even if you have 20 feet of 22 gauge inner conductor, which has 16 millihoms per foot resistance, you are only adding 320 milliohms.. or a third of an ohm to the circuit, which is insignificant to the input resistance of the amp.
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