Bose 1800-VI Owner's Manual page 10

4.0 Installation
For the XLR, pin 2 carries the + (hot, non-inverting) side of the signal, and pin 1 is
ground. To reference the input differential amplifier for the correct gain, short pin 3
to pin 1 (see Figure 5).
For the quick connect terminal block, pin 3 carries the + (hot, non-inverting) side of the
signal, and pin 1 is ground. Short pin 2 to pin 1 in order to reference the input differential
amplifier for the correct gain (see Figure 6).
Note
The gain remains the same regardless of whether the input is balanced or unbalanced.
10
Figure 5
1/4" XLR unbalanced input
connection.
Figure 6
Quick connect terminal block
unbalanced input connection.