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2003 Kia Optima

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Use our shopping filters to find the right 2/3/4-channel amp to power upgraded speakers properly.

Overview Upgrade your Stereo Upgrade your Speakers Add a Subwoofer Add an Amplifier Digital Sound Processors Audio Installation & Accessories Add a Backup Camera Dads & Grads Sale

Amps for Adding Speakers for 2003 Kia Optima

Some vehicles require an amp bypass module, a line-output converter like the NVX XLCA2 or AudioControl LC2i, or a DSP to integrate with your factory radio and avoid bass roll-off. Bass roll-off occurs when a factory radio's crossover is designed only for the original equipment speakers, resulting in a not complete signal being sent to your new aftermarket amp.

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Amplifier Class

An amplifier increases the power of the signal being fed to it by taking energy from its power supply and matching the signal but increasing its amplitude. Amplifiers use many different methods for converting these electrical signals and have been categorized into classes.

Class A/B: Greater than 50% of the input signal is amplified while the other percentage is “off”. These amplifiers have a small amount of current flowing through the output transistors all the time which almost eliminates crossover distortion. Class A/B has great sound quality but is not as efficient as class D. These amps are most commonly used to drive speakers.

Class D: Also known as switching amplifiers, class D amps have output transistors that are completely turned “on” or “off”. This means that when the transistors are on, there is almost no voltage across them but when they are off there is significant voltage but no current flowing through it which makes these amplifiers very efficient at the cost of sound quality. These amps are most commonly used to drive subwoofers.

Other Classes: You may see classes such as GH, bD, X, FD, etc. by some manufactures. These amplifiers tend to be either class A/B, D or a hybrid of the two but with improvements to their designs that can make them more efficient or offer better sound quality.
Number of Channels
Each channel on an amplifier will power one speaker using a positive and negative cable. There are various types of amplifiers, each designed to power a certain number of speakers. Monoblock amplifiers, also known as single channel, are designed to power one or more subwoofers. These amplifiers often have very high power ratings. On the other hand, multi-channel amplifiers power multiple speakers, usually at lower power ratings. 2-Channel and 4-Channel amplifiers can power car speakers or low powered subwoofers. Occasionally you might see a 5 or 6-channel amplifier that can power speakers and subwoofers at the same time. The most common setup is a monoblock amp to run subwoofers and a 4-channel amp to run door speakers. Check out our Knowledge Base for more information.
Total RMS Power Output
Total RMS power is measured by multiplying RMS power per channel by the number of channels, and is calculated at the lowest level of operating impedance.

RMS power is the amount of continuous power, measured in watts, that an amplifier produces is called RMS power. The higher the RMS figure, the louder and cleaner your music sounds.

The RMS output figure is much more accurate than the peak rating when comparing products.
Total Peak Power Output
The total peak power output is measured as the wattage per channel multiplied by the number of channels, and is calculated at the lowest level of operating impedance.

It is measured during a brief musical burst, such as a sudden drum accent. Some manufacturers display peak power ratings on the face of their products to increase the appeal.

The RMS power rating is more accurate, and we recommend using it for product comparison.
Minimum Impedance Unbridged
The lowest impedance the amplifier will handle when it is not bridged.
Minimum Impedance Bridged
The lowest impedance the amplifier will handle when it is bridged.
Remote bass/level controller
If the amp comes with a bass/gain remote you will be able to control the level of your bass from your dashboard. Typically bass remotes also include a 16-20 ft. wire for installation.
Preamp Outputs
Many amplifiers are equipped with RCA preamp outputs which pass the original music signal from the source to additional amplifiers. This is known as daisy chaining because the source connects to the first amp, and the first amp connects to the second amp, etc. The advantage to daisy chaining is you only need one 2-channel RCA cable to transfer the signal from the head-unit to the amplifier, and then one additional cable for each amp being daisy chained.
Built-in Crossover

A crossover is a type of filtering system that permits only certain frequencies to play. A Low-Pass (LP) crossover allows only frequencies below its setting to get through which is good in the case of some subwoofers. A High-Pass(HP) filter allows frequencies above its setting to pass through, this is normally used on speakers.

When a crossover is set to FULL it means no filtering is added and the full frequency spectrum is allowed through the amplifier. Filtering is important because feeding a speaker frequencies it cannot reproduce effectively creates distortion.

Speaker Level Inputs
Speaker level inputs are commonly referred to as high-level inputs and vice versa. This input type allows you to get your audio signal directly from the speaker wire in your vehicle, instead of using RCA cables. The advantage of this is factory integration, as most stock radios do not have RCA outputs to run amplifiers.
Maximum Input Gauge Size
This is the largest gauge wire that will fit into the power and ground terminals of this device. The lower the gauge number, the thicker the wire is. For example, a 4 gauge wire is thicker than an 8 gauge wire and thus has higher current carrying capacity. Always do your best to get this size wire to reduce the risk of damage to your components.
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JBL Apex PA454 with Belva 8 Gauge Amp Kit

180W RMS Apex Series Class-D Compact 4-Channel Powersports Amplifier

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JBL Apex PA454 with Belva 8 Gauge Amp Kit

180W RMS Apex Series Class-D Compact 4-Channel Powersports Amplifier

• 45 watts x 4 channel @ 4 ohm
• Total RMS Power: 180 watts
• Class D 4 ohm Stable 4-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 45 watts x 4 channel @ 4 ohm
• Total RMS Power: 180 watts
• Class D 4 ohm Stable 4-Channel Amplifier
• Includes Amplifier Wiring Kit

Alpine HDA-V90 with NVX 4 Gauge Amp Kit

900W RMS Status Series Class-D 5-Channel Car Amplifier

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Alpine HDA-V90 with NVX 4 Gauge Amp Kit

900W RMS Status Series Class-D 5-Channel Car Amplifier

• 75 watts RMS x 4 + 300 watts RMS x 1 at 4 ohm
• 100 watts RMS x 4 + 500 watts RMS x 1 at 2 ohm
• 200 watts RMS x 2 bridged at 4 ohm + 500 watts RMS x 1 at 2 ohm
• Total RMS Power: 900 watts
• Quick-connect power and speaker connectors
• Class D 2 ohm Stable 5-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 75 watts RMS x 4 + 300 watts RMS x 1 at 4 ohm
• 100 watts RMS x 4 + 500 watts RMS x 1 at 2 ohm
• 200 watts RMS x 2 bridged at 4 ohm + 500 watts RMS x 1 at 2 ohm
• Total RMS Power: 900 watts
• Quick-connect power and speaker connectors
• Class D 2 ohm Stable 5-Channel Amplifier
• Includes Amplifier Wiring Kit

NVX - Worth the Envy - Direct to Consumer Car Audio

Pioneer GM-DX975 with Amplifier Wiring Kit

2000 Watts Class D 5-Channel Amplifier w/ Gold-plated RCA Terminals and Bass Boost Remote

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Pioneer GM-DX975 with Amplifier Wiring Kit

2000 Watts Class D 5-Channel Amplifier w/ Gold-plated RCA Terminals and Bass Boost Remote

• 75 Watts RMS x 4 @ 4 ohm + 350 watts RMS x 1
• 100 Watts RMS x 1 @ 2 ohm + 600 watts RMS x 1
• 1200 Watts RMS x 1 @ 1 ohm
• 5-channel operation
• CEA-2006 Compliant/Preamp Outputs/LPF
• HQ Sound Parts
• Gold-plated RCA connections
• Includes Amplifier Wiring Kit
• 12-7/16"W x 2"H x 7-7/8"D

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• 75 Watts RMS x 4 @ 4 ohm + 350 watts RMS x 1
• 100 Watts RMS x 1 @ 2 ohm + 600 watts RMS x 1
• 1200 Watts RMS x 1 @ 1 ohm
• 5-channel operation
• CEA-2006 Compliant/Preamp Outputs/LPF
• HQ Sound Parts
• Gold-plated RCA connections
• Includes Amplifier Wiring Kit
• 12-7/16"W x 2"H x 7-7/8"D

Alpine R-A90S with NVX 4 Gauge Amp Kit

R Series 6/5/4/3 Channel Power Amplifier

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Alpine R-A90S with NVX 4 Gauge Amp Kit

R Series 6/5/4/3 Channel Power Amplifier

• 75 watts x 4 channel + 75 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel + 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm + 100 watts x 4 channel @ 2 ohm
• Total RMS Power:
• CEA-2006 Compliant
• Class D 2 ohm Stable 5-Channel Amplifier

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• 75 watts x 4 channel + 75 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel + 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm + 100 watts x 4 channel @ 2 ohm
• Total RMS Power:
• CEA-2006 Compliant
• Class D 2 ohm Stable 5-Channel Amplifier

JBL Club A5055 (AMPCBA5055AM) + NVX XKIT46

Class AB + D High Performance 5-Channel Amplifier + NVX XKIT46 4 Gauge 6-Channel Amp Wirring Kit

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JBL Club A5055 (AMPCBA5055AM) + NVX XKIT46

Class AB + D High Performance 5-Channel Amplifier + NVX XKIT46 4 Gauge 6-Channel Amp Wirring Kit

• Class AB + D Amp Technology
• 4 Ohm: 50 Watts RMS x 4 + 320 Watts RMS x 1
• Variable Crossover and Bass Boost
• Variable High and Low-Pass Filters
• Full on Board Protection

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• Class AB + D Amp Technology
• 4 Ohm: 50 Watts RMS x 4 + 320 Watts RMS x 1
• Variable Crossover and Bass Boost
• Variable High and Low-Pass Filters
• Full on Board Protection

DS18 SXE-1200.4/RD (Red) with Belva 4 Gauge Amp Kit

1200W Peak (400W RMS) Class AB SXE Series 4-channel Car Amplifier

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DS18 SXE-1200.4/RD (Red) with Belva 4 Gauge Amp Kit

1200W Peak (400W RMS) Class AB SXE Series 4-channel Car Amplifier

• 60 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: @ 4 ohm
• Total RMS Power: 400 watts
• Class A/B 2 ohm Stable 4-Channel-Channel Amplifier (Red)
• Includes Amplifier Wiring Kit

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• 60 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: @ 4 ohm
• Total RMS Power: 400 watts
• Class A/B 2 ohm Stable 4-Channel-Channel Amplifier (Red)
• Includes Amplifier Wiring Kit

Diamond Audio DMD600.4D with NVX 8 Gauge Amp Kit

600W RMS DMD Series Class-D 4-Channel Amplifier

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Diamond Audio DMD600.4D with NVX 8 Gauge Amp Kit

600W RMS DMD Series Class-D 4-Channel Amplifier

• 150 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 320 watts x 2 channel @ 4 ohm
• Total RMS Power: 600 watts
• Class D 2 ohm Stable 4-Channel-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 150 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 320 watts x 2 channel @ 4 ohm
• Total RMS Power: 600 watts
• Class D 2 ohm Stable 4-Channel-Channel Amplifier
• Includes Amplifier Wiring Kit

Rockford Fosgate R2-300X4 with Amplifier Wiring Kit

Rockford Fosgate 300W 4-Channel Class D Amplifier + Belva BAK44BL

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Rockford Fosgate R2-300X4 with Amplifier Wiring Kit

Rockford Fosgate 300W 4-Channel Class D Amplifier + Belva BAK44BL

• 50 Watts RMS x 4 @ 4 ohm
• 75 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 150 Watts
• CEA-2006 Compliant
•Variable On Board Punch EQ
• 1.9" x "6.8" x "10.1"

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• 50 Watts RMS x 4 @ 4 ohm
• 75 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 150 Watts
• CEA-2006 Compliant
•Variable On Board Punch EQ
• 1.9" x "6.8" x "10.1"

Crunch GP-1500.4 with Belva BAK44 Amp Kit

1500W RMS Class AB Ground Pounder Series 4 Channel Car Amplifier + 4 Gauge Premium (CCA) Complete 4-Channel Amplifier Wiring Kit with RCA up to 1200 Watts

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Crunch GP-1500.4 with Belva BAK44 Amp Kit

1500W RMS Class AB Ground Pounder Series 4 Channel Car Amplifier + 4 Gauge Premium (CCA) Complete 4-Channel Amplifier Wiring Kit with RCA up to 1200 Watts

• 185 watts x 4 channel @ 4 ohm
• 375 watts x 4 channel @ 2 ohm
• Bridged: 750 watts x 2 channel @ 4 ohm
• Total RMS Power: 1500 watts
• Class A/B 2 ohm Stable 4-Channel Amplifier

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• 185 watts x 4 channel @ 4 ohm
• 375 watts x 4 channel @ 2 ohm
• Bridged: 750 watts x 2 channel @ 4 ohm
• Total RMS Power: 1500 watts
• Class A/B 2 ohm Stable 4-Channel Amplifier

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American Bass GODFATHER 1000.2 with NVX 8 Gauge Amp Kit

1240W RMS Godfather Series Class-D 2-Channel Amplifier

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American Bass GODFATHER 1000.2 with NVX 8 Gauge Amp Kit

1240W RMS Godfather Series Class-D 2-Channel Amplifier

• 400 watts x 2 channel @ 4 ohm
• 620 watts x 2 channel @ 2 ohm
• Bridged: 1300 watts x 1 channel @ 4 ohm
• Total RMS Power: 1300 watts
• Class D 2 ohm Stable 2-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 400 watts x 2 channel @ 4 ohm
• 620 watts x 2 channel @ 2 ohm
• Bridged: 1300 watts x 1 channel @ 4 ohm
• Total RMS Power: 1300 watts
• Class D 2 ohm Stable 2-Channel Amplifier
• Includes Amplifier Wiring Kit

Pioneer GM-DX975 with NVX 4 Gauge Amp Kit

2000W Peak (800W RMS) GM Series Class-D 5-Channel Amplifier with Remote Bass Knob

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Pioneer GM-DX975 with NVX 4 Gauge Amp Kit

2000W Peak (800W RMS) GM Series Class-D 5-Channel Amplifier with Remote Bass Knob

• 75 watts x 4 channel + 350 watts x 1 channel @ 4 ohm
• 100 watts x 4 channel + 600 watts x 1 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm + 600 watts x 1 channel @ 2 ohm
• Total RMS Power: 800 watts
• Class D 2 ohm Stable 5-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 75 watts x 4 channel + 350 watts x 1 channel @ 4 ohm
• 100 watts x 4 channel + 600 watts x 1 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm + 600 watts x 1 channel @ 2 ohm
• Total RMS Power: 800 watts
• Class D 2 ohm Stable 5-Channel Amplifier
• Includes Amplifier Wiring Kit

Limited time!

NVX VAD11005 with Amplifier Wiring Kit

1100W Full Range Class D 5-Channel Car/Marine/Powersports Amplifier with Bass Remote

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NVX VAD11005 with Amplifier Wiring Kit

1100W Full Range Class D 5-Channel Car/Marine/Powersports Amplifier with Bass Remote

• 4 ohm: 80 watts x 4 chan. + 350 x 1 chan.
• 2 ohm: 125 watts x 4 chan. + 600 x 1 chan.
• Bridged, 4 ohm: 250 watts x 2 chan. + 600 x 1 chan.
• 5/4/2 Channel Operation
• Includes Amplifier Wiring Kit

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• 4 ohm: 80 watts x 4 chan. + 350 x 1 chan.
• 2 ohm: 125 watts x 4 chan. + 600 x 1 chan.
• Bridged, 4 ohm: 250 watts x 2 chan. + 600 x 1 chan.
• 5/4/2 Channel Operation
• Includes Amplifier Wiring Kit

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Rockford Fosgate Punch P400X4 with Amplifier Wiring Kit

400W Punch Series 4-Channel Stereo Class AB Car Power Amplifier (P400X.4)

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Rockford Fosgate Punch P400X4 with Amplifier Wiring Kit

400W Punch Series 4-Channel Stereo Class AB Car Power Amplifier (P400X.4)

• 50 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• 200 Watts RMS x 2 @ 4 ohm, Bridged
• Built In NOMAD "Real Time" Analog Computer
• 4/3/2/1 Channel Operation
• 4 Gauge Power and Ground Inputs
• MESHA3 Reduces MOSFET Temperatures for Improved Durability

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• 50 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• 200 Watts RMS x 2 @ 4 ohm, Bridged
• Built In NOMAD "Real Time" Analog Computer
• 4/3/2/1 Channel Operation
• 4 Gauge Power and Ground Inputs
• MESHA3 Reduces MOSFET Temperatures for Improved Durability

Rockford Fosgate Prime R2-500X4 + Belva BAK44 4 Gauge Amp Wiring Kit

Rockford Prime 500W 4-Channel Full Range Class D Amplifier + Belva BAK44

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Rockford Fosgate Prime R2-500X4 + Belva BAK44 4 Gauge Amp Wiring Kit

Rockford Prime 500W 4-Channel Full Range Class D Amplifier + Belva BAK44

• 75 Watts RMS x 4 @ 4 ohm
• 125 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 500 Watts
• CEA-2006 Compliant
• Top Mounted Control Panel
• 1.9" x "6.8" x "10.1"

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• 75 Watts RMS x 4 @ 4 ohm
• 125 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 500 Watts
• CEA-2006 Compliant
• Top Mounted Control Panel
• 1.9" x "6.8" x "10.1"

Pioneer GM-DX874 with NVX 4 Gauge Amp Kit

1200W Peak (600W RMS) GM Series Class-FD 4-Channel Amplifier with Remote Bass Knob

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Pioneer GM-DX874 with NVX 4 Gauge Amp Kit

1200W Peak (600W RMS) GM Series Class-FD 4-Channel Amplifier with Remote Bass Knob

• 100 watts x 4 channel @ 4 ohm
• 150 watts x 4 channel @ 2 ohm
• Bridged: 300 watts x 2 channel @ 4 ohm
• Total RMS Power: 600 watts
• Class D 1 ohm Stable 4-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 100 watts x 4 channel @ 4 ohm
• 150 watts x 4 channel @ 2 ohm
• Bridged: 300 watts x 2 channel @ 4 ohm
• Total RMS Power: 600 watts
• Class D 1 ohm Stable 4-Channel Amplifier
• Includes Amplifier Wiring Kit

Diamond Audio HXM800.4D with NVX 8 Gauge Amp Kit

800W RMS HXM Series Class-D 4-Channel Full Range Amplifier

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Diamond Audio HXM800.4D with NVX 8 Gauge Amp Kit

800W RMS HXM Series Class-D 4-Channel Full Range Amplifier

• 120 watts x 4 channel @ 4 ohm
• 200 watts x 4 channel @ 2 ohm
• Bridged: 400 watts x 2 channel @ 4 ohm
• Total RMS Power: 800 watts
• Class D 2 ohm Stable 4-Channel-Channel Amplifier
• Includes Amplifier Wiring Kit

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• 120 watts x 4 channel @ 4 ohm
• 200 watts x 4 channel @ 2 ohm
• Bridged: 400 watts x 2 channel @ 4 ohm
• Total RMS Power: 800 watts
• Class D 2 ohm Stable 4-Channel-Channel Amplifier
• Includes Amplifier Wiring Kit

Rockford Fosgate Power T600-4 + NVX XKIT44 4 Gauge Amp Wiring Kit

600W Power Series Compact 4-Channel Class AB Car Amplifier

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Rockford Fosgate Power T600-4 + NVX XKIT44 4 Gauge Amp Wiring Kit

600W Power Series Compact 4-Channel Class AB Car Amplifier

• 100W x 4-Chan. @ 4 ohm
• 150W x 4-Chan. @ 2 ohm
• 300W x 2 chan. @ 4 ohm
• 600W x 4-Chan. Max
• NOMAD protection circuitry: thermal, overload or short protection
• MOSFET power supply
• Includes NVX XKIT44 4 Gauge Amp Wiring Kit

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• 100W x 4-Chan. @ 4 ohm
• 150W x 4-Chan. @ 2 ohm
• 300W x 2 chan. @ 4 ohm
• 600W x 4-Chan. Max
• NOMAD protection circuitry: thermal, overload or short protection
• MOSFET power supply
• Includes NVX XKIT44 4 Gauge Amp Wiring Kit

Rockford Fosgate Power T400X4ad with Amplifier Wiring Kit

Compact 4-channel amplifier (4 x 100 Watts RMS @ 4 ohms)

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Rockford Fosgate Power T400X4ad with Amplifier Wiring Kit

Compact 4-channel amplifier (4 x 100 Watts RMS @ 4 ohms)

• 4 ohm: 100 watts x 4 chan.
• 2 ohm: 100 watts x 4 chan.
• Bridged, 4 ohm: 200 watts x 2 chan.
• Total Power: 400 Watts
• CEA-2006 Compliant
• C.L.E.A.N. Technology
• Fan Cooled

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• 4 ohm: 100 watts x 4 chan.
• 2 ohm: 100 watts x 4 chan.
• Bridged, 4 ohm: 200 watts x 2 chan.
• Total Power: 400 Watts
• CEA-2006 Compliant
• C.L.E.A.N. Technology
• Fan Cooled

Alpine S2-A55V with Belva 4 Gauge Amp Kit

540W RMS S-Series Class-D 5-Channel Car Amplifier

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Alpine S2-A55V with Belva 4 Gauge Amp Kit

540W RMS S-Series Class-D 5-Channel Car Amplifier

• 40 watts x 4 channel + 200 watts x 1 channel @ 4 ohm
• 60 watts x 4 channel + 300 watts x 1 channel @ 2 ohm
• Bridged: 120 watts x 2 channel @ 4 ohm + 300 watts x 1 channel @ 2 ohm
• Total RMS Power: 540 watts
• CEA-2006 Compliant
• Class D 2 ohm Stable 5-Channel Amplifier

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• 40 watts x 4 channel + 200 watts x 1 channel @ 4 ohm
• 60 watts x 4 channel + 300 watts x 1 channel @ 2 ohm
• Bridged: 120 watts x 2 channel @ 4 ohm + 300 watts x 1 channel @ 2 ohm
• Total RMS Power: 540 watts
• CEA-2006 Compliant
• Class D 2 ohm Stable 5-Channel Amplifier

Alpine KTA-450 with NVX 8 Gauge Amp Kit

4-Channel 200 Watt RMS Power Pack Amplifier

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Alpine KTA-450 with NVX 8 Gauge Amp Kit

4-Channel 200 Watt RMS Power Pack Amplifier

• Class D 4-channels Power Pack Amplifier
• Power Handling: 50W RMS x 4 @ 4ohm/45W RMS x 4 @ 2ohm
• Dynamic Peak Power (DPP)
• Frequency Response: 15-50 Hz
• CTA-2006 compliant
• Includes Amplifier Wiring Kit

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List price $467.99
-32% $319.95

In stock

Add to Cart

• Class D 4-channels Power Pack Amplifier
• Power Handling: 50W RMS x 4 @ 4ohm/45W RMS x 4 @ 2ohm
• Dynamic Peak Power (DPP)
• Frequency Response: 15-50 Hz
• CTA-2006 compliant
• Includes Amplifier Wiring Kit

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