Re: Pin 1 Problems
Posted: Mon Mar 10, 2014 3:45 pm
escapement:
Please qualify; are you using XLR to XLR leads (which if wired up correctly should be balanced leads) or 1/4" to XLR leads (unbalanced, which should be wired pin 1 wire shield to sleeve, pin 2 to tip, pin 3 also to sleeve at the 1/4" end)?
There is benefit in noise cancellation with pin 1 to plug shield tab, but it has to be at the right end.
Yes, it does make a difference which end is connected to the tab.
I can never remember for the life of me which end that should be.
Since occassionaly one might turn a lead over for a specific connection, I don't connect the tab to pin 1 ever when I make my leads up at either end.
However, at a show where my system was used, the SE asked for another short XLR to XLR because "that one is noisy". Turned out, when I had cut down a pre made lead to make a few shorter patch leads, I left the factory applied plug as it was, without looking at it. It had pin1 to tab connected. At the wrong end...
edit: IIRC the connection of pin 1 and tab at the right end (whichever one it be lol) is useful only if you are running gear from different power supplies that have different ground points. So if there is only one power distro wherever you are ie all power outlets are on the same ground point, the tabs simply don't require connection to pin 1.
Some people carry around DI's, that have earth lift on/off switching to eliminate that hum when there are different ground points, or, say, when 2 mixers are connected together and hum is introduced...
Please qualify; are you using XLR to XLR leads (which if wired up correctly should be balanced leads) or 1/4" to XLR leads (unbalanced, which should be wired pin 1 wire shield to sleeve, pin 2 to tip, pin 3 also to sleeve at the 1/4" end)?
There is benefit in noise cancellation with pin 1 to plug shield tab, but it has to be at the right end.
Yes, it does make a difference which end is connected to the tab.
I can never remember for the life of me which end that should be.
Since occassionaly one might turn a lead over for a specific connection, I don't connect the tab to pin 1 ever when I make my leads up at either end.
However, at a show where my system was used, the SE asked for another short XLR to XLR because "that one is noisy". Turned out, when I had cut down a pre made lead to make a few shorter patch leads, I left the factory applied plug as it was, without looking at it. It had pin1 to tab connected. At the wrong end...
edit: IIRC the connection of pin 1 and tab at the right end (whichever one it be lol) is useful only if you are running gear from different power supplies that have different ground points. So if there is only one power distro wherever you are ie all power outlets are on the same ground point, the tabs simply don't require connection to pin 1.
Some people carry around DI's, that have earth lift on/off switching to eliminate that hum when there are different ground points, or, say, when 2 mixers are connected together and hum is introduced...
