Bowers & Wilkins SA250 Mk2 Custom Installation page 9

Pre-amplifier
Connection to a stereo pre-amplifier
You can combine both left and right channels into one or
two subwoofers using a single SA250 Mk2. In this case, only
unbalanced connection is possible (above).
ISW-3 ISW-4
L R
1st
SA250 Mk2
unbalanced
Pre-amplifier
L
R
unbalanced
If you want to maintain stereo separation to the lowest
frequencies by having a subwoofer for each channel, you will
need a second SA250 Mk2. In this case, if the pre-amplifier
allows, you can use balanced connections (above right).
Otherwise, use unbalanced connections (above left).
ISW-3 ISW-4
balanced
balanced
2nd
SA250 Mk2
ISW-3 ISW-4
L
R
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