
Reattach large multi-pin connector from the (2)
woofers to the PC board as shown in above drawing.
Wire tie unused tap wires from transformer tightly so
Conductive parts cannot contact each other or other
parts and so that they can’t rattle with vibration.
Replace back panel onto back of enclosure and tighten
down plate firmly with original screws.
IS-MTCSBT300
03/2016
JBL Professional
8500 Balboa Blvd
Northridge, CA 91329
U.S.A.
12
13
14
WIRE LABELLING IN DIAGRAMS
ORIGINAL WIRES
(Being Removed)
A – RED
B - BLACK
TRANSFORMER SECONDARY
(Output to Speakers)
C – GREEN
“+” Output
D – YELLOW
“-” Output
TRANSFORMER PRIMARY
(From Input Terminals)
E – BLACK
Common
F – BLUE
Use for 300W@70V, N/C@100V
G – RED
Use for 150W@70V, 300W@100V
H – YELLOW
Use for 75W@70V, 150W@100V
I – ORANGE
Use for 37W@70V, 75W@100V
MULTI-CABLE TO SPEAKER DRIVERS
J – GREEN
K – WHITE
L – RED
M - BLACK