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2003 Nissan Altima

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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 Nissan Altima

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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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.
Amplifier Key Features
Amplifiers can offer a diverse array of features. If you select more than one feature, then you will view amplifiers that have ALL features selected. These include speaker-level inputs that facilitate seamless integration with factory audio systems, Bluetooth connectivity suitable for ATV/UTV or Classic vehicle setups, built-in DSPs that provide enhanced control over your audio signal, and a host of other functionalities to explore.
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.
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.
Series
Many brands group their products into series or lines of products to help customers know the level of quality (good, better, best for example). You can filter by series and the brand using our guided browsing.
Punch Series (32)
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ZXI Series (1)
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.
Sonic Certified Amplifier
Sonic Certified amplifiers have been tested by the experts at Sonic Electronix to meet or exceed the wattage ratings provided by the manufacturer. If this is marked as Yes, then you can trust the wattage ratings. If marked as No, then we have tested the amplifier and it did not meet the advertised wattage ratings. If marked as Not Tested, then the Sonic Electronix experts have not yet been able to test the amp.
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.

Amp Bluetooth Connectivity
This feature will tell you if the amplifier has the capability to connect to a Bluetooth device.
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Crunch CRA-1000.2

1000W RMS Class D CRA Series 2-Channel Compact Car Amplifier

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Crunch CRA-1000.2

1000W RMS Class D CRA Series 2-Channel Compact Car Amplifier

• 250 watts x 2 channel @ 4 ohm
• 500 watts x 2 channel @ 2 ohm
• Bridged: 1000 watts x 1 channel @ 4 ohm
• Total RMS Power: 1000 watts
• Class D 2 ohm Stable 2-Channel Amplifier

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DS18 SXE-4000.4D/RD

4000W Peak (1500W RMS) Class D SXE Series 4-Channel Car Amplifier

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DS18 SXE-4000.4D/RD

4000W Peak (1500W RMS) Class D SXE Series 4-Channel Car Amplifier

• 275 watts x 4 channel @ 4 ohm
• 430 watts x 4 channel @ 2 ohm
• Bridged: 750 watts x 2 channel @ 4 ohm
• Total RMS Power: 1500 watts
• Class D 2 ohm Stable 4-Channel-Channel Amplifier (Red)

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NVX XKIT44

$119.99

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Hifonics Brutus BRL800.4

800W RMS Class D Brutus BRL Series 4-Channel Car Amplifier

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Hifonics Brutus BRL800.4

800W RMS Class D Brutus BRL Series 4-Channel Car Amplifier

• 125 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 Amplifier

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Kicker KXMA400.2 (48KXMA4002)

500W Peak (400W RMS) Class D KXM Series 2-Channel Marine Amplifier

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Kicker KXMA400.2 (48KXMA4002)

500W Peak (400W RMS) Class D KXM Series 2-Channel Marine Amplifier

• 100 watts x 2 channel @ 4 ohm
• 200 watts x 2 channel @ 2 ohm
• Bridged: 400 watts x 1 channel @ 4 ohm
• Total RMS Power: 400 watts
• Class D 2 ohm Stable 2-Channel Amplifier

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List price $409.99
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Sundown Audio SAEv4-150.4

900W RMS Class AB SAE Series 4-Channel Car Amplifier (SAEv.4-150.4)

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Sundown Audio SAEv4-150.4

900W RMS Class AB SAE Series 4-Channel Car Amplifier (SAEv.4-150.4)

• 150 watts x 4 channel @ 4 ohm
• 225 watts x 4 channel @ 2 ohm
• Bridged: 450 watts x 2 channel @ 4 ohm
• Total RMS Power: 900 watts
• Class A/B 2 ohm Stable 4-Channel Amplifier

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Kicker KXMA800.4 (48KXMA8004)

1100W Peak (800W RMS) Class D KXM Series 4-Channel Marine Amplifier

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Kicker KXMA800.4 (48KXMA8004)

1100W Peak (800W RMS) Class D KXM Series 4-Channel Marine Amplifier

• 100 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 Amplifier

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Kicker KXMA1200.2 (48KXMA12002)

1500W Peak (1200W RMS) Class D KXM Series 2-Channel Marine Amplifier

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Kicker KXMA1200.2 (48KXMA12002)

1500W Peak (1200W RMS) Class D KXM Series 2-Channel Marine Amplifier

• 300 watts x 2 channel @ 4 ohm
• 600 watts x 2 channel @ 2 ohm
• Bridged: @ 4 ohm
• Total RMS Power: 1200 watts
• Class D 2 ohm Stable 2-Channel Amplifier

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List price $699.99
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Jensen JATWO

530W Peak (445W RMS) Class D JA Series 2-Channel Car Amplifier

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Jensen JATWO

530W Peak (445W RMS) Class D JA Series 2-Channel Car Amplifier

• 125 watts x 2 channel RMS @ 4 ohm
• 215 watts x 2 channel RMS @ 2 ohm
• Bridged: 445 watts x 1 channel RMS @ 4 ohm
• Total RMS Power: 445 watts
• Class D 2 ohm Stable 2-Channel Amplifier

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Wet Sounds SYN-DX2

750W Peak Class D SYN-DX Series 2 Channel Marine Amplifier

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Wet Sounds SYN-DX2

750W Peak Class D SYN-DX Series 2 Channel Marine Amplifier

• 200 watts x 2 channel @ 4 ohm
• 375 watts x 2 channel @ 2 ohm
• Bridged: 750 watts x 1 channel @ 4 ohm
• Total RMS Power: 750 watts
• Class D 2 ohm Stable 2-Channel Marine Amplifier

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• 200 watts x 2 channel @ 4 ohm
• 375 watts x 2 channel @ 2 ohm
• Bridged: 750 watts x 1 channel @ 4 ohm
• Total RMS Power: 750 watts
• Class D 2 ohm Stable 2-Channel Marine Amplifier

JL Audio VX800/8i

800W RMS Class D VXi Series 8 Channel Car Amplifier with Built-in DSP

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JL Audio VX800/8i

800W RMS Class D VXi Series 8 Channel Car Amplifier with Built-in DSP

• 75 watts x 8 channel @ 4 ohm
• 100 watts x 8 channel @ 2 ohm
• Bridged: 200 watts x 4 channel @ 4 ohm
• Total RMS Power: 800 watts
• Class D 2 ohm Stable 8-Channel Amplifier
• Includes integrated DSP

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Infinity DSP6840 (DSP6840AM)

1000W Peak (480W RMS) Class D DSP Series 8 Channel Car Amplifier with Digital Signal Processing

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Infinity DSP6840 (DSP6840AM)

1000W Peak (480W RMS) Class D DSP Series 8 Channel Car Amplifier with Digital Signal Processing

• 40 watts x 8 channel @ 4 ohm
• 60 watts x 8 channel @ 2 ohm
• Total RMS Power: 480 watts
• Class D 2 ohm Stable 8-Channel Amplifier

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List price $539.95
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Sundown Audio SALT-200.4

1400W RMS Class D SALT Series 4-Channel Full Range Car Amplifier

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Sundown Audio SALT-200.4

1400W RMS Class D SALT Series 4-Channel Full Range Car Amplifier

• 200 watts x 4 channel @ 4 ohm
• 325 watts x 4 channel @ 2 ohm
• Bridged: 700 watts x 2 channel @ 4 ohm
• Total RMS Power: 1400 watts
• Class D 2 ohm Stable 4-Channel Amplifier

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JBL Marine A754 (JBLMA754AM)

400W RMS Class H Marine Series 4-Channel Car Amplifier

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JBL Marine A754 (JBLMA754AM)

400W RMS Class H Marine Series 4-Channel Car Amplifier

• 75 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm
• Total RMS Power: 400 watts
• Class H 2 ohm Stable 4-Channel-Channel Amplifier

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• 75 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm
• Total RMS Power: 400 watts
• Class H 2 ohm Stable 4-Channel-Channel Amplifier

Crunch DR-2525.4D

2525W Peak Class D V-Drive Series 4-Channel Car Amplifier

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Crunch DR-2525.4D

2525W Peak Class D V-Drive Series 4-Channel Car Amplifier

• 320 watts x 4 channel @ 4 ohm
• 630 watts x 4 channel @ 2 ohm
• Bridged: 1260 watts x 2 channel @ 4 ohm
• Total RMS Power:
• Class D 2 ohm Stable 4-Channel Amplifier

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Kicker WXA1000.4 (49WXA10004)

2000W Class D Warhorse Series 4-Channel Full Range Car Amplifier with Diagnostic Tools

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Kicker WXA1000.4 (49WXA10004)

2000W Class D Warhorse Series 4-Channel Full Range Car Amplifier with Diagnostic Tools

• 250 watts x 4 channel @ 4 ohm
• 450 watts x 4 channel @ 2 ohm
• Bridged: 900 watts x 2 channel @ 4 ohm
• Total Peak Power: 2000 watts
• Class D 2 ohm Stable 4-Channel Amplifier

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Crunch CRA-950.4

950W RMS Class D CRA Series 4-Channel Compact Car Amplifier

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Crunch CRA-950.4

950W RMS Class D CRA Series 4-Channel Compact Car Amplifier

• 115 watts x 4 channel @ 4 ohm
• 235 watts x 4 channel @ 2 ohm
• Bridged: 475 watts x 2 channel @ 4 ohm
• Total RMS Power: 950 watts
• Class D 2 ohm Stable 4-Channel Amplifier

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List price $130.00
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NVX XKIT44

NVX XKIT44

$119.99

$83.99

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• 115 watts x 4 channel @ 4 ohm
• 235 watts x 4 channel @ 2 ohm
• Bridged: 475 watts x 2 channel @ 4 ohm
• Total RMS Power: 950 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Sound Extreme by ECOXGEAR SEI-AMP30041

300W RMS Class D 4 Channel High Definition Marine and Powersports Amplifier

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Sound Extreme by ECOXGEAR SEI-AMP30041

300W RMS Class D 4 Channel High Definition Marine and Powersports Amplifier

• 75 watts x 4 channel @ 4 ohm
• Bridged: 150 watts x 2 channel @ 2 ohm
• Total RMS Power: 300 watts
• Class D 4 ohm Stable 4-Channel Amplifier

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List price $399.99
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• 75 watts x 4 channel @ 4 ohm
• Bridged: 150 watts x 2 channel @ 2 ohm
• Total RMS Power: 300 watts
• Class D 4 ohm Stable 4-Channel Amplifier

Cerwin-Vega XED8005D

1000W Peak (660W RMS) Class D XED Series 5 Channel Car Amplifier with Bass Remote

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Cerwin-Vega XED8005D

1000W Peak (660W RMS) Class D XED Series 5 Channel Car Amplifier with Bass Remote

• 65 watts x 4 channel + 200 watts x 1 channel @ 4 ohm
• 90 watts x 4 channel + 300 watts x 1 channel @ 2 ohm
• 700 watts x 1 channel @ 1 ohm (subwoofer output)
• Bridged: @ 4 ohm
• Total RMS Power: 660 watts
• Class D 2 ohm Stable 5-Channel Amplifier

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List price $335.99
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Sundown Audio SALT-1700.5

1700W RMS Class D SALT Series 5-Channel Full Range Car Amplifier

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Sundown Audio SALT-1700.5

1700W RMS Class D SALT Series 5-Channel Full Range Car Amplifier

• 125 watts x 4 channel + 480 watts x 1 channel @ 4 ohm
• 220 watts x 4 channel + 800 watts x 1 channel @ 2 ohm
• 1300 watts x 1 channel @ 1 ohm
• Total RMS Power: 1700 watts
• Class D 1 ohm Stable 5-Channel Amplifier

Save 30% off an NVX XKIT06 Amp Kit at Checkout!
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• 125 watts x 4 channel + 480 watts x 1 channel @ 4 ohm
• 220 watts x 4 channel + 800 watts x 1 channel @ 2 ohm
• 1300 watts x 1 channel @ 1 ohm
• Total RMS Power: 1700 watts
• Class D 1 ohm Stable 5-Channel Amplifier

JBL STAGE GT 80021 (STAGEGT80021AM)

800W Peak (260W RMS) Class D Stage GT Series 2-Channel Car Amplifier

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JBL STAGE GT 80021 (STAGEGT80021AM)

800W Peak (260W RMS) Class D Stage GT Series 2-Channel Car Amplifier

• 80 watts x 2 channel @ 4 ohm
• 130 watts x 2 channel @ 2 ohm
• Bridged: 260 watts x 1 channel @ 4 ohm
• Total RMS Power: 260 watts
• Class D 2 ohm Stable 2-Channel Amplifier

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• 80 watts x 2 channel @ 4 ohm
• 130 watts x 2 channel @ 2 ohm
• Bridged: 260 watts x 1 channel @ 4 ohm
• Total RMS Power: 260 watts
• Class D 2 ohm Stable 2-Channel Amplifier

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    FAQ for Multi-channel Amplifiers for Adding Speakers in 2003 Altima

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