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6. The amplifier should be grounded
with a short, heavy gauge wire
connected directly to the car at a
bare metal surface, preferably
scraped body sheet metal. Do not
use factory ground locations, seat
bolts, or brackets that are
spotwelded.
7. Always fuse your power connection
within 8 to 10 inches of the battery
terminal. Use a fuse or circuit
breaker rated slightly more than the
on-board fuse(s) of the
amplifier(s). The gauge of power
wire used should take into account
the total current draw of the
system, and the length of wire
used. IASCA and other auto sound
competition organizations have
charts available for this; you can
also find a chart in the MECP study
guide. Minimum wire gauge recom-
mendations for the individual ampli-
fiers are listed on the specification
page. Always use the same gauge
wire for the amplifier ground that
you use for the power wire. Be sure
to examine the battery ground
cable of the vehicle, and if neces-
sary, upgrade it by adding an addi-
tional ground wire that is the same
gauge as the amplifier power wire.
Remember, the amplifier can only
deliver its rated output when it is
not current limited by the power
and ground supply wires.
8. This amplifier is designed to drive a
speaker load that measures from 2
to 4 ohms. Keep in mind that heat
is the long-term enemy of automo-
tive electronics and the lower your
speaker load, the more heat is
generated. For low impedance
speaker applications or restricted
ventilation installations, an external
cooling fan may be advisable.
9. Battery and ground connections to
the vehicle should be made with
crimped ring terminals of the appro-
priate size (surface area is what
counts); soldering the terminals
after crimping is also recom-
mended.
10. Due to the high-frequency MOSFET
switching power supply, filtering the
power cable is not generally
required (remember that the amp
can’t deliver full output if the power
supply is restricted). Proper
grounding of the signal source is
mandatory for the amplifier to
reach its performance peak. If the
RCA inputs are not grounded
adequately via the signal source,
electrical noise from the vehicle
may be picked up in the system.