nandric
Dear Dover, Which method should be used to connect the XLR
connectors? Should the ground wire from pin 5 in the Din5 connector
be split in two such that each can be soldered to the pin 1 on the
XLR connectors? Or should only the (floating) shield of both
channels be connected to the pin 1 on the XLR connectors?
Nandric - for all phono both balanced and unbalanced the arm earth ( 5th pin ) should be a separate wire which you connect to preamp chassis. This simply grounds the arm itself and has nothing to do with the cartridge signal.
Floating shields on the signal cables should only be connected to earth at one end.
In the RCA's at the preamp end I connect the floating shield ( assuming a twisted pair plus shield construction ) to the chassis by cutting the connection to the RCA and soldering a tail for connection to the preamp chassis. This reduces the opportunity for noise collected by the shield to enter the phono signal in a single ended system.
In this arrangement you end up with 3 earth leads to connect to the preamp chassis - tonearm earth/ground plus left and right channel floating shield earth/ground.
XLR's have a separate -ve signal and earth/ground in a balanced system. Therefore you only need to ensure the shield is connected to the earth/ground pin which is already separated from the -ve signal. The tonearm end is left floating ( not connected ).
