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Find powerful 4 channel amps for name brand manufacturers such as Kicker, JVC, Pioneer and more. Four channel amplifiers allow you to have more installation options.
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4-Channel Amplifiers Total Peak Power Output: Up to 500 watts, Bass/Gain Remote: No

480W 4 Channel DJ Series Class D Marine Amplifier

• RMS Power: 80W x 4 @ 4 ohms, 120W x 4 @ 2 ohms
• Total Peak Power: 480W
• Variable Low Pass Filter
• Dimensions: 7" W x 9.88" L x 2" H

$169.99

IN STOCK

True 800W RMS, Full Range Class D 4-Channel Amplifier (JAD-800.4)

• 4 ohms: 125 watts x 4-Chan.
• 2 ohms: 200 watts x 4-Chan.
• Bridged, 4 ohms: 400 x 2 chan.
• Pulse Width Modulated MOSFET Power Supply
• 4/3/2 Channel Operation

25% off Amp Kit with purchase!

$259.99

IN STOCK

Micro-V Series 400W RMS 4-Channel Bridgeable Micro Class D Compact Car Amplifier (MVPA.4)

• The size of a postcard with 400 Watts True RMS Output!
• • MVP Series 4-Channel Micro Class D Amplifier
• 50W x 4-Chan. @ 4 ohms
• 100W x 4-Chan. @ 2 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 8 Gauge Power and Ground Inputs
• Extremely Small Footprint!

FREE 8 Gauge Amp Kit with Select Amplifiers Purchase!

$199.99

IN STOCK

300W XC Series Micro 4-Channel Class-D Compact Design Car Amplifier

• 50W x 4-Chan. @ 4 ohms
• 75W x 4-Chan. @ 2 ohms
• 3-Way System Protection
• 4-Channel Operation
• 8 Gauge Power and Ground Inputs
• Micro Size Amplifier for Maximizing Space Saving Applications

Save 35% on an 8 Gauge Amp Kit with Purchase!

$94.99

IN STOCK

400W 4-Channel Class D Prime Series Amplifier

• 75W x 4-Chan. @ 4 ohms
• 100W x 4-Chan. @ 2 ohms
• 200W x 2 Chan. @ 4 ohms Bridged
• Variable Bass Boost
• Variable High-Pass Crossover
• CEA-2006 Compliant

$164.99

IN STOCK

300 Watts Punch Series Boosted Rail Compact 4-Channel Amplifier

• RMS 75 x 1 @ 4 ohms
• Features Rockford Fosgate's Class-BR Topology
• CEA-2006 Compliant
• Ultra Compact Chassis
• Boosted Rail Design
• Dimensions: 6.75"L x 4.25"W x 1.53"H

Save 20% on an RF Amp Kit and get an Extended Warranty!

$179.99

IN STOCK

600W Bomber Series 4-Channel Class D Digital Amplifier

• RMS Power: 80W x 4 @ 4 ohms, 150W x 4 @ 2 ohms
• Dual Zone , operate two separate devices to two separate stages (front vs rear)
• Ultra Compact High Density Aluminium Alloy Chassis
• Direct FET Power Mosfet Output Stage
• Dimensions: 4.02"W x 8.7"L x 1.4"H

$139.99

IN STOCK

800W 4-Channel PA D Series Car Amplifier

• 125W x 4-Chan. @ 4 ohm
• 200W x 4-Chan. @ 2 ohm
• 400W x 2-Chan. Bridged
• Level Control
• High-Pass Filter
• Adjustable High-Pass & Low-Pass Frequencies

25% off Amp Kit with purchase!

$249.99

IN STOCK

640W 4 Channel Brutus Series Class AB Amplifier

• RMS Power: 80W x 4 @ 4 ohms, 160W x 2 @ 2 ohms
• Total Peak Power: 640W
• Variable High and Low Pass Filters
• Dimensions: 9.8" W x 14.7" L x 2.4" H

$149.99

IN STOCK

240W RMS 4-Channel GM Series Bridgeable Class AB Car Amplifier

• RMS: 40W x 4 @ 4 ohms, 60W x 4 @ 2 ohms, 120W x 2 @ 4 ohm
• Total Peak Power: 240W
• CEA-2006 Compliant
• Dimensions: 12-1/2"W x 8-1/2"L x 2-3/8"H

Save 25% on a 4 Gauge Amp Kit with Purchase!

$89.99

IN STOCK

400W 4-Channel Gothic Series Class AB Car Amplifier

• 4 ohms: 45 watts x 4-Chan.
• 2 ohms: 75 watts x 4-Chan.
• Max power output: 400 watts
• MOSFET power supply
• 4/3/2 Channel Operation

Save 25% on an 8 Gauge Amp Kit with Purchase!

$54.99

IN STOCK

300W 4-Channel Class D V-Power Series Compact Car Amplifier

• RMS Power: 50W x 4-Chan. @ 4 ohms, 75W x 4-Chan. @ 2 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 8 Gauge Power and Ground Inputs
• Same Power in a 40% Smaller Chassis

FREE 100% Copper, True 8 Gauge Wiring Kit wi/ Select Amps

$199.95

IN STOCK

Only 1 Left!

360W 4-Channel Nautical Series Class SQ Marine Amplifier

• 60W x 4-Chan. @ 4 ohms
• 90W x 4-Chan. @ 2 ohms
• 180W x 2 Chan. @ 4 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 4 Gauge Power and Ground Inputs
• 3-Way Protection Circuitry

$109.95

IN STOCK

320W 4 Channel Brutus Series Class AB Amplifier

• RMS Power: 40W x 4 @ 4 ohms, 80W x 4 @ 2 ohms
• Total Peak Power: 320W
• Variable High and Low Pass Filters
• Dimensions: 9.8" W x 11" L x 2.4" H

Save 25% on a 4 Gauge Amp Kit with Purchase!

$129.99

IN STOCK

Only 2 Left!

520W 4-Channel iON Series Class D Full-Range Digital Stereo Bridgeable Amplifier

• 100W x 4-Chan. @ 4 ohms
• 130W x 4-Chan. @ 2 ohms
• 260W x 2 Chan. @ 4 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 4 Gauge Power and Ground Inputs
• Surface Mount Technology (SMT)

Save 25% on a 4 Gauge Amp Kit with Purchase!

$119.99

IN STOCK

1600W 4-Channel Brutus (BRX) Series Super A/B Class Amplifier

• RMS: 200W x 4 @ 4 ohms, 200W x 4 @ 2 ohms, Bridged 800W x 2 @ 4 ohm
• Total RMS Power: 1600W
• Ultra-Fi MOSFETS power supply
• Heavy duty aluminum alloy heat-sink
• Illuminated Hifonics logo

Save 25% on a 4 Gauge Amp Kit with Purchase!

$239.99

IN STOCK

600W 4-Channel Class D Prime Series Amplifier

• 100W x 4-Chan. @ 4 ohms
• 150W x 4-Chan. @ 2 ohms
• 300W x 2 Chan. @ 4 ohms Bridged
• Variable Bass Boost
• Variable High-Pass Crossover
• CEA-2006 Compliant

$259.95

IN STOCK

500W 4/3 Channel Class AB Power Amplifier

• RMS Power: 40W x 4 @ 4 ohms, 60W x 4 @ 2 ohms
• Total Peak Power: 250W
• CEA-2006 Compliant
• 7-7/8"W x 12-3/8"L x 2-3/16"H

Save 25% on a 4 Gauge Amp Kit with Purchase!

$99.99

IN STOCK

Only 3 Left!

320W 4-Channel iON Series Class D Full-Range Digital Stereo Bridgeable Amplifier (i3204)

• 60W x 4-Chan. @ 4 ohms
• 80W x 4-Chan. @ 2 ohms
• 160W x 2 Chan. @ 4 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 4 Gauge Power and Ground Inputs
• Surface Mount Technology (SMT)

$99.95

IN STOCK

400W RMS 4-Channel Full Range Class D Marine Amplifier

• 4 ohms: 75 watts x 4 chan.
• 2 ohms: 100 watts x 4 chan.
• Bridged, 4 ohms: 200 watts x 2 chan.
• Uv Resistant And Salt-Fog Marine Protection

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

$299.95

IN STOCK

Only 2 Left!

400W PDX Series 4-Channel Power Density Digital Class D Car Amplifier

• RMS Power: 100W x 4-Chan. @ 4 ohms
• 400 Watts RMS
• Class D
• Variable High-Pass and Low-Pass Filter
• Blue LED Power/Status Indicator
• Compact Size

FREE True 4 Gauge OFC Amplifier Install Kit with Purchase!

$499.95

IN STOCK

Only 1 Left!

600W 4-Channel Digital Low Profile Series Class D Car Amplifier (Made in Korea)

• RMS: 100W x 4 @ 4 ohms, 150W x 4 @ 2 ohms
• Total Peak Power: 400W
• Pulse Width Modulated MOSFET Power Supply
• 4-Way Protection Circuitry
• Dimensions: 3"W x 5.9"L x 1.5"H

Save 25% on an 8 Gauge Amp Kit with Purchase!

$109.95

IN STOCK

Only 2 Left!

400W RMS JX Series 4-Channel Class D Full-Range Amplifier

• Peak: 70W x 4 @ 4 ohms, 100W x 4 @ 2 ohms, 200W x 2 @ 4 ohms Bridged
• Unregulated PWM switching type power supply
• Class D Circuitry
• Defeatable 12 dB / octave filter
• Speaker-level (high-level) inputs with included harness
• Dimensions: 7.68"W x 9.05"L x 2.09"H

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

25% off Amp Kit with purchase!

$249.99

IN STOCK

Only 2 Left!

280W 4-channel Class D Full-Range Amplifier

• 50W x 4 @ 4ohms , 70W x 4 @ 2ohms
• NexD™ ultra-high-speed switching design
• Black powder-coated finish
• Gasketed cover for the controls
• Stainless steel hardware for durability
• Accepts RCA (low-level) & Speaker-level (high-level) signal
• Signal to Noise Ration: 89.5 dB

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

10% off JL Audio Amp Kit with purchase!

$229.99

IN STOCK

Only 1 Left!

280W 4-Channel Marine Amplifier

• RMS Power: 4 ohms: 60 watts x 4 / 2 ohms: 70 watts x 4
• Frequency Response: 80 Hz - 20 kHz
• Speaker-level inputs
• LED power indicators

Free Gift: 1.0 Farad Capacitor with Amp Purchase!

$199.95

IN STOCK

Only 2 Left!

320W 4-Channel GS Series Compact Car Amplifier w/ 3-year warranty!

• Free 3-Year Warranty
• 4 ohms: 70 watts x 4-Chan.
• 2 ohms: 80 watts x 4-Chan.
• Bridged, 4 ohms: 160 watts x 2 chan.
• Pulse Width Modulated MOSFET Power Supply
• LED Power (green) and Protect (red) Indicators

FREE 8 Gauge Amp Kit with Select Amplifiers Purchase!

$249.99

IN STOCK

450W 4-Channel eXcelon Series Full Range Power Car Amplifier

• 4 ohms: 60 watts x 2 chan. + 100 watts x 2 chan.
• 2 ohms: 75 watts x 2 chan. + 150 watts x 2 chan.
• Bridged, 4 ohms: 60 watts x 2 chan. + 300 watts x 1 chan.
• Pulse Width Modulated MOSFET Power Supply

$279.99

IN STOCK

Only 1 Left!

400W 4-Channel Class A/B High Fidelity Q Series Car Amplifier

• RMS: 75W x 4 @ 4 ohms, 100W x 4 @ 2 ohms
• 200W x 2 Channel @ 4 Ohms Bridged
• Fixed Bass Boost
• Variable Low Pass Filters
• Optically Isolate MOSFET Power Supply
• 3 Way System Protection Circuitry

$395.99

AVAILABLE

Ships at Later Date

300W RMS 4-Channel Slash v3 Series Class A/B Full-Range Amplifier

• RMS: 75W x 1 @ 4 ohms, 75W x 1 @ 2 ohms, 75W x 1 @ 1.5 ohms
• Total RMS Power: 300W
• R.I.P.S. (Regulated, Intelligent Power Supply)
• Dual N-Channel MOSFET power supply
• Absolute Symmetry™ Class A/B Circuit
• 13.4"L x 9.25"W x 2.36"H

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

10% off JL Audio Amp Kit with purchase!

$599.95

IN STOCK

4-Channel 85W PDR Series Class D Car Amplifier

• RMS Power: 85W x 4 @ 4 ohms, 125W x 2 @ 2 ohms, 250W x 2 @ 4 ohms, Bridged
• Preamp Outputs
• Dimensions: 9"W x 7.12"L x 2.8"H

$399.95

IN STOCK

Only 3 Left!

640W 4-Channel Z-Line Series Class SQ A/B Amplifier

• RMS: 80W x 4 @ 4 ohms, 160W x 4 @ 2 ohms, Bridged 320W x 2 @ 4 ohms.
• Fluid-FETS hand selected insulated MOSFETS
• Q-Stasis preamp stage with wide input range
• Top mounted controls for simple setup & adjustment
• Frequency Response: 10 - 45,000 Hz

Free XKIT44 OFC Amplifier Install Kit with Purchase!

$299.99

IN STOCK

600W PDX Series 4-Channel Power Density Digital Class D Car Amplifier

• RMS Power: 150W x 4-Chan. @ 4 ohms
• 600 Watts RMS
• Class D
• Variable High-Pass and Low-Pass Filter
• Blue LED Power/Status Indicator
• Compact Size

FREE True 4 Gauge OFC Amplifier Install Kit with Purchase!

$749.95

IN STOCK

400W Marine Series 4-Channel Power Density Digital Amplifier

• RMS Power: 100W x 4-Chan. @ 4 ohms, 100W x 4-Chan. @ 2 ohms
• 200W x 2 chan. @ 4 ohms
• 4/3/2 channel operation
• Coated to protect unit against harsh marine environment
• Compact and stackable design

$599.95

IN STOCK

Only 2 Left!

400W 4 Channel Digital Compact Series Class D Car Amplifier (Made in Korea)

• RMS: 60W x 4 @ 4 ohms, 85W x 4 @ 2 ohms, 200W x 2 @ 4 ohm, Bridged
• Total Peak Power: 400W
• Pulse Width Modulated MOSFET Power Supply
• Variable Bass Boost
• 4-Way Protection Circuitry
• Dimensions: 4.7"W x 7.9"L x 1.6"H

$109.99

IN STOCK

Only 2 Left!

600W RMS 4-Channel Full Range Class D Marine Amplifier

• 4 ohms: 100 watts x 4 chan.
• 2 ohms: 150 watts x 4 chan.
• Bridged, 4 ohms: 300 watts x 2 chan.
• Uv Resistant And Salt-Fog Marine Protection

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

$449.99

IN STOCK

300W 4-Channel PXA-Series Power Amplifier

• RMS: 25W x 2 @ 4 ohms, 50W x 2 @ 2 ohms, 100W x 2 @ 1 ohm
• Total RMS power output: 200 Watts
•Weather-resistant with a conformal-coated circuit board
•Specifically designed for motorized vehicles
• No-rust, stainless-steel mounting hardware and a single Molex plug

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

$299.95

IN STOCK

Only 2 Left!

320W 4-Channel Z-Line Series Class SQ A/B Amplifier

• RMS: 40W x 4 @ 4 ohms, 80W x 4 @ 2 ohms, Bridged 160W x 2 @ 4 ohms.
• Fluid-FETS hand selected insulated MOSFETS
• Q-Stasis preamp stage with wide input range
• Top mounted controls for simple setup & adjustment
• Frequency Response: 15 - 45,000 Hz

$249.99

IN STOCK

Only 2 Left!

480W RMS 4-Channel BT Series Bluetooth Marine Amplifier

• Built-in professional Bluetooth® signal processor module
• Corrosion-resistant ABYC compliant connectors
• Meets or exceeds ASTM d4329 (UV exposure)
• Full MOSFET DC-DC PWM power supply
• Bluetooth Range: Up to 30 feet (10m)
• Bluetooth audio and remote turn on signals can be passed to other amplifiers

$313.99

IN STOCK

Only 2 Left!

320W 4-Channel Marine Amplifier

• 60W x 4-Chan. @ 4 Ohms
• 80W x 4-Chan. @ 2 Ohms
• 160W x 2 Chan. @ 4 Ohms
• 320W RMS
• MOSFET Power Supply
• Preamp RCA outputs
• Thermal, Voltage and Short Protection Circuitry

$109.95

OUT OF STOCK

Universal Class D 4-Channel Head Unit Power Pack for Use with all Aftermarket & Factory Receivers

• RMS Power: 45W x 4-Chan. @ 4 Ohm
• Adjustable Gain Switch
• Plug-and-Play
• CEA-2006 Compliant

$149.95

OUT OF STOCK

900W Phantom Series Class D Full Range 4-Channel Amplifier

• RMS Power: 145 watts x 4 @ 4 ohms, 225 watts x 4 @ 2 ohms
• 450W RMS x 2 Channel @ 4 ohms Bridged
• Tri-Mode Capable
• 3-Way System Protection
• Variable Low-Pass Crossover
• Variable High-Pass Crossover
• Band-Pass Crossovers
• Input Source Selector

$199.99

OUT OF STOCK

400W 4-Channel Class AB Evolution Series Car Amplifier

• 50W RMS x 4-Channels
• MOSFET Power Supply
• High/Low Level Inputs
• Fixed High/Low Pass Filters
• 3-Way System Protection Circuitry

$44.99

OUT OF STOCK

200W 4-Channel Class AB Chaos EXXtreme Series Stereo Bridgeable Car Amplifier

• 50W x 2 Chan. @ 4 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 8 Gauge Power and Ground Inputs
• Heavy Duty Aluminum Heat Sink

$39.99

OUT OF STOCK

400W Max, 4-Channel MR Series Marine Amplifier

• 4 ohms: 50 watts x 4 chan.
• 2 ohms: 100 watts x 4 chan.
• Pulse Width Modulated MOSFET Power Supply
• LED power (green) and Protect (red) Indicators
• Variable Bass Boost (0 to +12 dB bass boost at 50 Hz)

$54.99

OUT OF STOCK

400W eXcelon Series 4-Channel Reference XR Stereo Bridgeable Class D Car Power Amplifier (XR4004)

• 75W x 4-Chan. @ 4 ohms
• 100W x 4-Chan. @ 2 ohms
• 200W x 2 Chan. @ 4 ohms
• 3-Way System Protection
• 4/3/2/1 Channel Operation
• 4 Gauge Power and Ground Inputs
• Extremely Thin Design

$249.99

OUT OF STOCK

SPS-610C Type-S Component Speakers + SPS-610C Type-S Coaxial Speakers + Cerwin-Vega B4 4-Ch. Class-D Amplifier + TruConnex Amp Wiring Kit

• 4 ohms: 80 watts x 4 chan.
• 1" Silk Dome Tweeter
• Woofer Mounting Depth: 2-1/4"
• Tuned Poly-Mica Cone
• 4 Ohms Impedance
• Dual Zone , operate two separate devices to two separate stages (front vs rear)
• Ultra Compact High Density Aluminium Alloy Chassis
• Direct FET Power Mosfet Output Stage
• Dimensions: 4.02"W x 8.7"L x 1.4"H

$324.95

OUT OF STOCK

600W Vega Series 4-Channel Class D Car Amplifier

• RMS Power: 100W x 4 @ 4 ohms, 175W x 4 @ 2 ohms,
• Bridged, 4 ohms: 300 watts x 2 chan.
• Tiffany Style Low Level RCA Inputs
• Dimensions: 7.25"W x 10.47"L x 1.93"H

$249.99

IN STOCK

Only 1 Left!

CSS65 CS Series Component Speakers + CS65 CS Series Coaxial Speakers + Cerwin-Vega B4 4-Ch. Class-D Amplifier + TruConnex Amp Wiring Kit

• 4 ohms: 80 watts x 4 chan.
• 4 ohms Impedance
• Polypropylene Cone
• Ribbed, Polyester Foam Surround
• Balanced Dome Tweeter
• Dual Zone , operate two separate devices to two separate stages (front vs rear)
• Ultra Compact High Density Aluminium Alloy Chassis
• Direct FET Power Mosfet Output Stage
• Dimensions: 4.02"W x 8.7"L x 1.4"H

$351.99

OUT OF STOCK

2-Way Thunder Series Component System + 2-Way Thunder Series Coaxial System + Cerwin-Vega B4 4-Ch. Class-D Amplifier + TruConnex Amp Wiring Kit

• 4 ohms: 80 watts x 4 chan.
• 1" Soft Dome Tweeter
• Polypropylene Cone and Rubber Surround
• Dual Zone , operate two separate devices to two separate stages (front vs rear)
• Ultra Compact High Density Aluminium Alloy Chassis
• Direct FET Power Mosfet Output Stage
• Dimensions: 4.02"W x 8.7"L x 1.4"H

$359.95

OUT OF STOCK

Thunder Series Component Speaker System + Thunder Series Coaxial Speakers + Cerwin-Vega B4 4-Ch. Class-D Amplifier + TruConnex Amp Wiring Kit

• 4 ohms: 80 watts x 4 chan.
•Silk Soft Dome Tweeter
• Polypropylene Woofer Cone
• 2-Way Crossover With Adjustable Tweeter Level
• Dual Zone , operate two separate devices to two separate stages (front vs rear)
• Ultra Compact High Density Aluminium Alloy Chassis
• Direct FET Power Mosfet Output Stage
• Dimensions: 4.02"W x 8.7"L x 1.4"H

$369.99

OUT OF STOCK

600 Watt Hydro?Tech™ Series Full Range 4-Channel Class D Marine Amplifier

• RMS: 110W x 4 @ 4 ohms, 150W x 4 @ 2 ohms, 300W x 2 @ 4 ohm
• Total RMS Power: 600 watts
• Completely Sealed Salt Water Compliant High Mass Heat Sink
• Accent Stripes for Customization (paintable)
• Wet Sounds™ Extensive Crossover Network
• Dimensions: 7.20" W x 8.00" L x 2.80" H

VIP Guarantee - FREE 2-Day Shipping,
10% Rewards, Extended Warranty and more!

$449.99

OUT OF STOCK

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Related Categories

Amplifier Wiring Kits
Get all the cables, wires, and hardware you need to install your new car audio amplifier with one of these power amp kits. Amplifier wiring kits come with your basic power and ground cables, as well as other necessary wires. Select complete amplifier kits will include speaker wire, RCA interconnect cables, and more! To make sure you get the kit that is best designed for your car audio system, scroll down to the bottom of this page for the buying guide.
Capacitors
Car audio capacitors are a great addition to any aftermarket audio system that is in need of a little extra power. Capacitors store a temporary electrical charge that can be released during periods of extra power strain. If a vehicle has dimming headlights when music is played, a capacitor could solve that problem.
Sound Processors
For those who want the most out their car audio system, a quality sound processor is a must. After some slight adjustments, your systems will sound like it has been professionally tuned and optimized. Tune your system to perfection with these crossovers, equalizers, and bass drivers. Click here to learn more about digital sound processors and to find out which type would be best for your car audio system.

4-Channel Amplifiers Information

A 4-channel amplifier is the best way to power a complete set of new car speakers. These amplifiers are designed to power four door speakers, although the right & left channels can usually be bridged to offer a wide range of wiring options. Commonly, the rear channels will be bridged to power a small subwoofer while the front channels are used for the front speakers. Some audiophile installations use these amplifiers to bi-amp a pair of component speakers – in these setups, each tweeter and midwoofer is powered from their own channel. Four channel amplifiers mostly utilize class A/B circuitry for the best possible sound quality, but the last few years have seen a huge rise in the popularity of full-range class D amps. These amplifiers are prized for their compact chassis, and advances in technology have made them sound almost indistinguishable from their A/B counterparts. 4-Channel amplifiers also frequently feature preamp outputs or signal pass-thru, allowing you to provide signal to a subwoofer amp without running another RCA cable to your head unit.