Polk PA D4000.4

Polk PA D4000.4

$649 $584

4 Channel Amplifier

SKU: PA D4000.4 Categories: ,

Super efficient class D bridgable 4-channel mobile audio amplifier

The PA D4000.4 amplifier is capable of bridging two full-range channels into a single full range channel with higher output power. For instance, one front and one rear channel will increase the output power from 125W per channel to 400W per channel (for a 4 ohm load). The most common hookups for the PA D4000.4 would be four full-range channels, two full-range channels and a bridged sub, or two bridged subwoofers.

Super-efficient class D design—Runs much cooler than conventional amps.

High-speed MOSFET—Switching power supply.

Toroidal transformers—Help keep the amplifier’s sleek design under 2-inch tall while ensuring plenty of clean, efficient power.

Protection—Thermal, DC offset, reverse DC voltage and short circuit protection.

Nickel-plated wire terminals & RCA connectors—Ensure maximum signal transfer.

Front & rear level controls—Adjust the gain of the front and rear channels to match the output voltage from your head unit.

Low-pass & high-pass frequency controls—Enables you to adjust crossover overlap for better blending of speakers.

Front & rear BPF, FULL, HPF switches—Selects full range, high pass filter, or bandpass filter to dial in your speaker blending.

Channel mode switch (ST/4Ch)—In the stereo position, the amplifier will send the same signal to front and rear channels.

Stainless steel hardware—Used throughout won’t corrode in humid environments.


Total Frequency Response 20Hz-20kHz
Signal-to-noise (Referenced to rated power) 105 dBA
Distortion at Rated Power <0.1 %
Minimum Impedance Bridged 4 ohms
Minimum Impedance Not Bridged 2 ohms
Protection Circuitry Thermal, DC offset, reverse DC voltage and short circuit; fuses: one 40 Amp and one 35 Amp ATC
High Pass Filter
Filter Slope 12dB/octave
Filter Frequency 20Hz-4kHz (front)/20Hz-4kHz(rear)
Low Pass Filter
Filter Slope 12dB/octave
Filter Frequency 50Hz-5kHz(front)/50Hz-5kHz(rear)
Effective Damping Factor >100
Max Sensitivity 200mV-6V dB


Cabinet Dimensions
Height 1 13/16″ (4.60cm)
Width 10 15/16″ (27.78cm)
Depth 6 3/4″ (17.14cm)
Product Weight (each) 5.0 lbs. pounds
Without Panels
Height 1 13/16″ (4.60cm)
Width 10 15/16″ (27.78cm)
Depth 6 3/4″ (17.14cm)

Amplifier Specs

Channels 4
Channel Notes Bridgeable Class D MOSFET
12V & Ground Cable Gauge 4AWG

Amplifier Power Specs

RMS Power at 14.4V
Watts per channel NOT bridged @ 1 kHz
4 ohms 125 watts
2 ohms 200 watts
Watts per channel bridged
4 ohms 400 watts

Additional Information

Weight 4 kg
Dimensions 40 x 40 x 20 cm