M&S Systems 8-Ohm - Manual (Page 9)

The only difference between new and existing
construction is the order in which the process is done
(steps 1, 2 and 3). In existing construction the speaker
hole is cut, the wire is run to the volume control box,
and the speaker is connected to the wiring and installed
in the wall. You are ready to complete the process using
steps 4, 5, and 6 for new construction.
Figure 2
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