Precision Power PCX 250 Stereo Amplifier User Manual


 
If your grand total current draw is over 100 amps (or total output power is over
600 watts), you are probably exceeding the capability of your charging system.
Dimming lights and fluctuating voltage are solid indicators that you need to
upgrade your alternator, battery, or both. Keep in mind that your amplifiers simply
convert electrical energy to acoustical energy, and any electrical deficiency will
compromise the performance of your sound system. For more information about
charging system upgrades, see your local authorized PrecisionPower Dealer or
call PrecisionPower Technical Support at 1-800-62POWER x 229.
Locate an area near the amplifier(s) that is metal and clean an area about the size
of a quarter to bare metal. Inspect the area around and underneath to be sure you
won't drill into wires, brake or fuel lines, etc. Drill a pilot hole in the middle of this
area. Terminate the ground wire with a ring connector and attach it to the bare
metal using a #8 sheet metal screw and washer or preferably, a bolt, nut and a
star washer (not supplied). We suggest crimping and soldering this connection.
After the connection is complete, coat the area (on both sides) with silicone or
some similar material to prevent rust from developing on the bare metal. If your
grand total current draw is over 50 amps (or total output power is over 300 watts),
you should run a separate ground wire beside your power wire from the battery
to the amplifier(s). Keep the ground and power wires as close together as possi-
ble, and use the same gauge wire for both. This will ensure that you have a good
ground path, and may eliminate such potential problems as engine noise and
overheated amplifiers.
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The ability to run stereo speakers while simultaneously running a mono output
from the same amplifier is accomplished by running the stereo speakers normally
and tapping into the appropriate wires for the "mixed mono" channel (left channel
positive for the positive speaker wire and right channel negative for the negative
speaker wire). Speaker impedance should be no lower than 2 Ohms on the stereo
channels and 4 ohms on the mono channel.
NOTE: Passive crossovers must be used for "mixed mono" operation. Choose a
low pass crossover around 100Hz for your subwoofer, then choose a high pass
crossover for your stereo channels. The high pass crossover must be at the same
or slightly higher frequency than the low pass crossover to maintain the correct
impedance. See your PrecisionPower dealer or call 1-800-62POWER for more
information about passive crossovers.
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