LA Audio SPX20 - Manual (Page 6)

Page 6
Pin 1 = Screen Pin 2 = Hot (+)
Pin 3 = Cold (-)
PUSH
Fig 2.6.3: Pin arrangement for XLR inputs on the SPX20
Pin 1 Screen Signal ground
Pin 2 Hot Signal +
Pin 3 Cold Signal -
For unbalanced operation join pins 1 and 3 and connect to Screen (signal
ground) and use pin 2 as Hot (signal +).
Input 1 also has a pair of front panel inserts on TRS jacks which are wired
as follows -
Sleeve
Screen Ring
Cold (-)
Tip
Hot (+)
Fig 2.6.3: Pin arrangement TRS jack inserts on Input 1
Tip Hot Signal +
Ring Cold Signal -
Sleeve Screen Signal ground
For unbalanced operation join Ring and sleeve and connect to screen
(signal ground) and use Tip as Hot (signal +).
Plugging a mono jack into these inserts effectively unbalances the
connection.
Sleeve
Screen Tip
Hot (+)
Fig 2.6.4: Mono jack pin arrangement
Tip Hot (signal +)
Sleeve Screen (signal ground)