[Elecraft] Balanced Mic to Unbalanced Connection Follow Up Question

[Jim Brown]

Correcting Joe's typo, Mic audio is present between pins 2 and 3, NOT 
between 2 and 1.

73, Jim K9YC

On 6/9/2020 2:54 PM, Joe Subich, W4TV wrote:
> 
>  > So which is correct?
> 
> They are electrically equivalent.
> 
> Pin 2 of the XLR connection is Mic+
> Pin 3 of the XLR connection is Mic-
> Pin 1 of the XLR connection is the cable shield (ground).
> 
> Mic audio is present between pins 2 and 1.
> 
> Pin 1 is nothing more than a shield and should be independently
> connected to the *chassis at the jack*.
> 
> Good quality XLR cables use a *TWISTED PAIR* for pins 1 and 2.
> That twisted pair is shelf shielding - particularly good for
> rejecting hum. Connecting a shield in parallel with the wire
> for pin 3 "unbalances" the twisted pair and makes it much
> more susceptible to hum and RFI - particularly when the shell
> of the 3.5mm plug/jack is not tied to the chassis/case of the
> transceiver.