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hum on videos

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Jaspreet Singh:

--- Quote from: Brian Jojade on November 09, 2023, 12:09:46 PM ---Hum is typically introduced either as a ground loop from devices on 2 different ground points, or through external noise inducted into the signal line.

Those arbitrary distance numbers are based on pretty much nothing.

With a proper balanced signal, running parallel lines long distance can be done without issue.  Unbalanced cables are more susceptible to interference, but with good shielding and grounding you can be fairly noise free.

Poor connections on balanced connections can mean losing one side of the balanced signal. This results in a loss of volume that can be adjusted for and seemingly be a non issue, but at that point, you're now subject to noise interference.

Ground loop issues with bad ground connections means devices may be at different ground potentials and hum may seemingly come and go.  Creating a solid ground is a solution, as well as transformer isolation of the devices so that it doesn't matter that they are at different ground potentials.  Transformer isolation is generally the most reliable solution.

--- End quote ---

Great info thanks!
My question now is, would running regular speaker wire (just a red and black) be more vulnerable than a balanced XLR cable or would a speaker wire be safe too as long as it is wired properly?

Scott Holtzman:

--- Quote from: Jaspreet Singh on November 14, 2023, 11:19:16 PM ---Great info thanks!
My question now is, would running regular speaker wire (just a red and black) be more vulnerable than a balanced XLR cable or would a speaker wire be safe too as long as it is wired properly?

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It's more complex than that.  We run shielded single ended and balanced connections which can benefit from shielding but can get away without it though in practice we always use shielded cable in entertainment application on signals that are low in voltage like a microphone.  These signals are more susceptible to interference because it is easy for the induced interference to be at a greater level than the actual signal. 


A speaker on the other hand takes quite a bit of power to produce an audible signal.  Inducing that much power would be very difficult. 


Does this make sense?

Jaspreet Singh:

--- Quote from: Scott Holtzman on November 14, 2023, 11:35:32 PM ---

Does this make sense?

--- End quote ---

Yes, thank you

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