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Attaching the loudspeaker/baffle securely in place with screws:
Using JBL’s MTC-300BB12 Backbox
– MTC-300BB12 is compatible with two common mounting systems for in
-
stalling the loudspeaker/baffle to the backbox.
Either
of these mounting systems may be utilized. Screws are included
with the MTC-300BB12 backbox.
Using A Different-Brand Compatible Backbox
-- Screwholes in the metal baffle are provided corresponding with
two common mounting systems. Utilize the system that works with that particular backbox.
Mounting Option #2
Using 4 pcs 4 mm Machine Bolts
2 Points at Each Side
1 Point at Each End
Mounting Option #1
Using 6 pcs #10 Sheet Metal Screws
1 Point at Each Corner
4 pcs 4 mm x 14 mm
Threaded Machine Bolts
(included with JBL MTC-300BB12 backbox).
Use with Backbox’s 4 Threaded
Insert Points, shown above.
6 pcs #10 x 0.75 inch
Sheet Metal Screws
(included with JBL MTC-300BB12 backbox)
Use with Backbox’s 6 Speed Nuts (also called Clip Nuts or
Tinnerman Nuts), shown above.
4
JBL Professional
8500 Balboa Boulevard, P.O. Box 2200
Northridge, California 91329 U.S.A.
361089-001
8/05
MTC-300BB12
Backbox Shown
– OR –