Instruction manual

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20
21
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23
20. AC Line Cord: The grounded power
cord should only be plugged into a
grounded power outlet that meets all
applicable electrical codes and is compat-
ible with the voltage, power, and frequen-
cy requirements stated on the rear panel.
Do not attempt to defeat the safety
ground connection.
21: Fuse: The fuse protects the amplifier
from damages caused by a faulty AC
power source and/or other problems. If
the fuse blows, replace it ONLY with the
same size and type. If fuses continue to
fail, check the AC source – if the source is
okay, contact your Crate dealer for serv-
ice information.
22. Impedance Switch: Use this switch
to set the amplifier’s output impedance to
match the impedance of the speakers.
The impedance of the speakers inside the
amplifier is 16 ohms. The switch is set at
the factory to the 16 ohm position. When
external speaker cabinets are used (see
#23), this switch must be set to match the
total impedance of the cabinets. Use the
tip of a small flatblade screwdriver to slide
the switch to the proper position. Use the
chart below to figure the total impedance
of multiple cabinets connected in parallel:
IMP. OF # OF TOTAL
CABINET
CABINETS IMPEDANCE
16Ω 28Ω
32Ω 216Ω
32Ω 48Ω
23. Speaker Jacks: The amplifier is
shipped from the factory with one of these
jacks connected to the internal speakers
of the amplifier. The remaining jack may
be used to connect the amplifier to one or
more extension speakers. Alternately, the
internal speakers may be bypassed by
unplugging the factory-installed connec-
tor and using the jacks to connect the
amplifier to one or more external speaker
cabinets.
NOTE: The impedance switch (#22)
MUST match the total impedance of all
cabinets connected to the amplifier. Refer
to the impedance chart following item #22
to determine the correct setting.
The Rear Panel: