XLR Cables - Technical Discussion: Difference between revisions

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To further confuse things, the Wikipedia reference to [http://en.wikipedia.org/wiki/XLR_connector#XLR3_connectors EIA Standard RS-297-A] says that third pin (actually, numbered pin 1) is used for chassis ground -- but doesn't reference the SIGNAL ground at all -- but one of the referenced links points to a [http://www.clarkwire.com/PinOutXLRBalanced.htm manufacturer's diagram] which shows pin 1 as a SIGNAL connection, and the shell is not connected to chassis ground!

Ideally, the external shell is connected to the cable shielding at both ends, and is connected to an independent "shield ground path" on the equipment at both ends, so that the "antenna" (induced) currents from that cable shield never enter the "reference ground" (signal ground) used by the circuitry at each end of the cable.

Ideally, the external shell is connected to the cable shielding at both ends, and is connected to an independent "shield ground path" on the equipment at both ends, so that the "antenna" (induced) currents from that cable shield never enter the "reference ground" (signal ground) used by the circuitry at each end of the cable. All three pins on the connecter are connected; if pin 1 is not connected, that could be an unsafe cable to use!

However, as a user -- do you know what the manufacturer has done with the "shell/chassis" ground and the "signal ground"??? Not knowing that ... and knowing that manufacturers disagree on the best practices for doing so ... one can get all sorts of variations of grounding, as in Figure 5 in that [http://www.rane.com/note151.html Rane article].

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 To further confuse things, the Wikipedia reference to [http://en.wikipedia.org/wiki/XLR_connector#XLR3_connectors EIA Standard RS-297-A] says that third pin (actually, numbered pin 1) is used for chassis ground -- but doesn't reference the SIGNAL ground at all -- but one of the referenced links points to a [http://www.clarkwire.com/PinOutXLRBalanced.htm manufacturer's diagram] which shows pin 1 as a SIGNAL connection, and the shell is not connected to chassis ground!
-Ideally, the external shell is connected to the cable shielding at both ends, and is connected to an independent "shield ground path" on the equipment at both ends, so that the "antenna" (induced) currents from that cable shield never enter the "reference ground" (signal ground) used by the circuitry at each end of the cable.
+Ideally, the external shell is connected to the cable shielding at both ends, and is connected to an independent "shield ground path" on the equipment at both ends, so that the "antenna" (induced) currents from that cable shield never enter the "reference ground" (signal ground) used by the circuitry at each end of the cable.  All three pins on the connecter are connected; if pin 1 is not connected, that could be an unsafe cable to use!
 However, as a user -- do you know what the manufacturer has done with the "shell/chassis" ground and the "signal ground"???  Not knowing that ... and knowing that manufacturers disagree on the best practices for doing so ... one can get all sorts of variations of grounding, as in Figure 5 in that [http://www.rane.com/note151.html Rane article].