Hafler JF2000 Owner's Manual page 7

Why
How
Bridged Mono
What is Bridging?
may wish to drive biamplified pairs of speakers with
identical signals if the speakers have internal crossovers.
'You may wish to drive multiple speakers which would be too
low in impedance if driven together (under 4 Ohms).
Set the INPUT switch to MONO (out). This feeds the right
and left channel power amplifier section from the left input
signal jack. Connect the speakers the same as you would for
standard stereo. Leave all other switches in the standard
position (IN) unless you have other reasons for using them.
(Refer to Figure 3)
Left positive (+) terminal (red) to Left Speaker
L e f t negative (-) terminal (black) to Left Speaker negative (-)
Right positive (+) terminal (red) to Right Speaker positive (+)
Right negative (-) terminal (black) to Right Speaker negative (-)
"Bridging" an amplifier means using two amplifier channels
to drive a single speaker. Normally, one terminal of the
speaker is driven by an amplifier section, and the other
terminal is grounded (that is, current is returned to the driving
amplifier). When a speaker load is driven by a bridged
amplifier pair, each terminal of the speaker is driven by a
separate amplifier
Figure 3
section.
5
positive (+)