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Amplifier Design: Class-D amplifiers boast
higher efficiency, produce much less heat, and draw less current than
traditional Class-AB amps. The PDX series is Alpine's totally new
super-efficient power density design of full range class-D amps. They combine
MOSFET power supplies, MOSFET final outputs, and a
thermal management processor, along with a 4-Layer Glass Epoxy PC Board to
create a high-end sound quality without the bulky heat sinks required by most
amps with this much power.
Alpine's unique STAR (Signal Transit for Accurate Response) Circuit PCB design
provides a single common ground for all amp sub-blocks, preventing ground
interference and minimizing internal noise.
For wiring convenience all the inputs and outputs on the amp are on one
The amplifier comes with a certificate that lists the RMS
power output of the individual amplifier. It also lists the model number, serial
number, test date, and the test conditions (14.4 volts, 4 ohms).
The PDX series amps use a new Speaker Quick Connect plug to attach the speaker
wires to the amp. Bare speaker wire, up to 8 gauge, is held in place by a set
screw, the Quick Connect plug then plugs into the amp. Like an RCA jack, the
Quick Connect plug uses a center positive layout, so it fits two ways and both
maintain correct polarity.
Stack Amps: Because the PDX series design
generates so little heat, up to three amps can be stacked and bolted together.
All three amps in the series, PDX-2.150, PDX-4.150, and PDX-1.1000 share the
same footprint, so they can be stacked together.
Notes: When stacking multiple amplifiers, do not install vertically or at an incline. Any stack installation other than parallel to the
vehicle floor, invalidates the warranty.
The top mounted LED Power/Status indicator glows blue when operating
normally and red when one of the protection circuits engages.
Protection Circuits: This
amplifier includes protection circuits to prevent damage due to the following
- ambient temperature too high
supply current too high
short to ground
Controls (front of unit):
Once set, the controls are covered by a door.
- Crossover Mode switch: set to HP (high pass),
OFF (full range) or
LP (low-pass), separate controls for the front and rear channels
- Crossover Frequency:
rotary controls used to select the crossover frequency, separate controls
for the front and rear channels, variable from 30 to
- Gain control: rotary
controls used to set the amplifier's gain according the level of the incoming
signal, separate controls for the front and rear channels, continuously variable from 0.2V to 4.0V
- Input switch:
set to 1+3/2+4 (input 1 and 3 summed to feed channel 3, inputs 2 and 4
summed to feed channel 4, this makes channels 3 and 4 non-fading), 3/4
(channels 3 and 4 fed by inputs 3 and 4, maintains fader when head unit has
front and rear line outputs), or 1/2 (channels 3 and 4 fed by inputs 1 and
2, no Y-adapters needed when head unit has only one pair of line outputs)
Inputs and Outputs (rear of
- Power and Ground terminals: power and ground terminals are
gold plated set screw terminals, will accept up to 4 gauge bare wire, Alpine
recommends 6 gauge wire minimum
- Remote Turn-on terminal:
gold plated set screw terminal, will accept up to 10 gauge bare wire
Speaker terminals: each
of the 4 speaker outputs uses Alpine's Speaker Quick Connect plug
Line Level Input: 4 female RCA jacks, left and right
for the front and rear channels, gold plated