Audio Note M3 Phono Owner's Information page 9

Balanced The M3 Phono is equipped with custom designed and manufactured
output transformers, which utilize an improved output and grounding
scheme to provide the best possible connection to the power amplifier.
Below is a description of the various cable and connection options: -
RCA
OUTPUT
SOCKET
BALANCED /
SINGLE ENDED
SWITCH
The pin configuration for all Audio Note (UK)
XLR / BALANCED connections is as follows: -
PIN 1
PIN 2
PIN 3
The
simultaneously; select the appropriate output using the toggle switch.
When using an amplifier with a true balanced input, the
ʻBALANCED / SINGLE ENDEDʼ switch may be set in either position.
When set to the ʻBALANCEDʼ position, the centre tap of the output
transformer secondary is connected to the preamplifierʼs ground.
When set in the ʻSINGLE ENDEDʼ (unbalanced) position, the
secondary ʻfloatsʼ in relation to the preamplifier ground. This provides
the option of either a low or high common mode impedance to ground
at the preamplifier output. Experiment with both positions to achieve
the lowest background hum from the system.
CONNECTION continued...
Ground / Shield
Positive / Send
Negative / Return
balanced and unbalanced
XLR MALE
OUTPUT
2
1
3
outputs cannot be used