This product is a vintage Polk model and is not available for sale, but it may still be available in some stores as a closeout or used product. The following text is taken from the original sales brochure for this product and does not reflect current availability. If you happen to have any question or concerns about this product, or any other Polk Audio product, feel free to contact our Customer Service Department at 1-800-377-7655 Monday - Friday, 9am - 5:30pm EST

PA500.4 (4/3/2 channels)

High performance 4-channel mobile audio amplifier

Available Finishes:

Pure Performance.

Features like a continuously variable 12dB/octave low-pass crossover, switchable subsonic filter 24dB/octave, switchable 180° phase inversion. and a remote subwoofer level control function enable you to fine-tune your setup to optimize its performance in a variety of configurations.

PA500.4 Features:

125 Watts x 4 continuous, 200 x 4 dynamic power (2 ohm load), 4 channel mode.

250 Watts x 2 (4 ohm) continuous power, 2 channel mode.

CEA-2006 compliant specifications for true, accurate power ratings.

4-channel, dual bridge-mono (2-channel), or dual simultaneous stereo/mono operation provide a variety of configurations and setups: 4-channel for front and rear speakers; 2 speakers and a sub; 2 subwoofers; or 2 subs and 4-channels in passive-tri mode.

2 ohm stable 4-channel operation.

High-speed MOSFET switching power supply and high current bipolar output transistors pump maximum voltage and high current to your speakers or subwoofers.

Double layer fiberglass epoxy printed circuit boards for more rigidity, less shrinkage and a smaller overall amp footprint.

6-way Smart System Protection (SSP) circuits

Fully adjustable (50-500Hz) 12 dB/octave high- or low-pass crossover. Defeatable for full range (flat) operation.

Switchable 8 dB bass boost at 40Hz for extra bass thump.

Variable input gain optimizes match with different signal sources (250mv to 7.5V).

RCA outputs (front channels only) for easy daisy chaining of other amplifiers.

Mounting hardware with rubber isolation grommets and extra fuses included.

Light bar/fan output-Connect an optional LED light bar or cooling fan for custom installations.

Multi-color status LED gives instant information on amplifier operation.

Remote subwoofer level adjuster for rear channels included.


Signal-to-noise (Referenced to rated power)98 dBA
Protection Circuitry2 x 40 amp fuses, Power and Ground-Reversal Protection, Thermal and Short Protection, Current Overdraw and Low Impedance Protection circuits 
Subsonic FilterNo 
High Pass Filter
Filter Slope12 dB/Octave 
Filter Frequency50-500 Hz 
Low Pass Filter
Filter Slope12 dB/Octave 
Filter Frequency50-500 Hz 
Effective Damping Factor>150 
Input Impedance20 k ohms
Max Sensitivity250 mV to 7.5 dB


Product Weight (each)16.00 pounds
With Panels
Height2 9/16" (6.51cm) 
Width18" (45.72cm) 
Depth10 1/4" (26.04cm) 

Amplifier Specs

Bass Boost Characteristics+ 8 dB @ 40 Hz Hz
12V & Ground Cable Gauge8 AWG Minimum 


Total Shipping Weight18.00 pounds

Amplifier Power Specs

RMS Power at 14.4V
Watts per channel NOT bridged @ 1 kHz
4 ohms90 watts
2 ohms125 watts
Watts per channel bridged
4 ohms250 watts
Dynamic Power at 14.4V
Watts per channel NOT bridged @ 1 kHz
2 ohms200 watts

Specifications, dimensions and features subject to change without notice. For more information call us at 1-800-377-7655 (USA and Canada). Outside of North America call +1 (410) 358-3600.

PA500.4 Media

PA500.4 Literature

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PA500.4 (4/3/2 channels) Accessories