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2003 Audi S8

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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 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 Audi S8

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.
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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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JL Audio XDM800/8

800W RMS XDM Series Class D 8-Channel Car and Marine Amplifier

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JL Audio XDM800/8

800W RMS XDM Series Class D 8-Channel Car and Marine Amplifier

• 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-Channel Amplifier

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• 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-Channel Amplifier

JL Audio XDM400/4

400W RMS Class D XDM Series 4 Channel Car and Marine Amplifier

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JL Audio XDM400/4

400W RMS Class D XDM Series 4 Channel Car and Marine 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 D 2 ohm Stable 4-Channel Amplifier

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Infinity Primus 90041A (PRIMUS90041A)

1480W Peak (520W RMS) Class D Primus Series 4-Channel Car Amplifier

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Infinity Primus 90041A (PRIMUS90041A)

1480W Peak (520W RMS) Class D Primus Series 4-Channel Car Amplifier

• 90 watts x 4 channel @ 4 ohm
• 130 watts x 4 channel @ 2 ohm
• Bridged: 260 watts x 2 channel @ 4 ohm
• Total RMS Power: 520 watts
• Class D 2 ohm Stable 4-Channel Amplifier

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• 90 watts x 4 channel @ 4 ohm
• 130 watts x 4 channel @ 2 ohm
• Bridged: 260 watts x 2 channel @ 4 ohm
• Total RMS Power: 520 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Rockford Fosgate Punch Marine PM600X4

600W RMS Class AB Punch Series 4 Channel Marine Amplifier

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Rockford Fosgate Punch Marine PM600X4

600W RMS Class AB Punch Series 4 Channel Marine Amplifier

• 75 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 A/B 2 ohm Stable 4-Channel Amplifier

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Deaf Bonce Machete MLA-160.4

900W RMS Class D Machete Series 4-Channel Car Amplifier

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Deaf Bonce Machete MLA-160.4

900W RMS Class D Machete Series 4-Channel Car Amplifier

• 160 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 D 2 ohm Stable 4-Channel Amplifier

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NVX XKIT44

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• 160 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 D 2 ohm Stable 4-Channel Amplifier

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Deaf Bonce Avatar ABR-460.4

460W RMS Class AB Buran Series 4-Channel Car Amplifier

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Deaf Bonce Avatar ABR-460.4

460W RMS Class AB Buran Series 4-Channel Car Amplifier

• 115 watts x 4 channel @ 4 ohm
• 230 watts x 4 channel @ 2 ohm
• Bridged: 460 watts x 2 channel @ 4 ohm
• Total RMS Power: 460 watts
• Class A/B 2 ohm Stable 4-Channel Amplifier

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NVX XKIT44

$119.99

$83.99

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MB Quart NA2-320.4

320W Peak Class D Nautic Series 4 Channel Marine and Powersports Amplifier

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MB Quart NA2-320.4

320W Peak Class D Nautic Series 4 Channel Marine and Powersports Amplifier

• 40 watts x 4 channel @ 4 ohm
• 80 watts x 4 channel @ 2 ohm
• Total Power: 320 watts
• Class D 2 ohm Stable 4-Channel Amplifier

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• 40 watts x 4 channel @ 4 ohm
• 80 watts x 4 channel @ 2 ohm
• Total Power: 320 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Wet Sounds HTM-6

900W RMS Class D HTM Series 6 Channel Marine Amplifier with LED Backlit Badge

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Wet Sounds HTM-6

900W RMS Class D HTM Series 6 Channel Marine Amplifier with LED Backlit Badge

• 85 watts x 6 channel @ 4 ohm
• 150 watts x 6 channel @ 2 ohm
• Bridged: 300 watts x 3 channel @ 4 ohm
• Total RMS Power: 900 watts
• Class D 2 ohm Stable 6-Channel Marine Amplifier

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• 85 watts x 6 channel @ 4 ohm
• 150 watts x 6 channel @ 2 ohm
• Bridged: 300 watts x 3 channel @ 4 ohm
• Total RMS Power: 900 watts
• Class D 2 ohm Stable 6-Channel Marine Amplifier

MB Quart PA1-400.4

400W Peak Class D Premium Pro Series 4-Channel Car Amplifier

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MB Quart PA1-400.4

400W Peak Class D Premium Pro Series 4-Channel Car Amplifier

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

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

Hifonics HCM-400.4D Colossus Mini

400W Peak Class D Colossus Mini Series 4 Channel Amplifier

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Hifonics HCM-400.4D Colossus Mini

400W Peak Class D Colossus Mini Series 4 Channel Amplifier

• 50 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm
• Class D 2 ohm Stable 4-Channel Amplifier

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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

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NVX XKIT06

NVX XKIT06

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MTX MUD100-4

800W Peak (400W RMS) Class D MUD Series 4 Channel Marine and Powersports Amplifier

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MTX MUD100-4

800W Peak (400W RMS) Class D MUD Series 4 Channel Marine and Powersports Amplifier

• 50 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 D 2 ohm Stable 4-Channel Amplifier

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NVX VADM5 v2 (VADM5v2)

1500W Peak (750W RMS) Class D V-Series 5-Channel Car/Marine/Powersports Amplifier with Bass Remote

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NVX VADM5 v2 (VADM5v2)

1500W Peak (750W RMS) Class D V-Series 5-Channel Car/Marine/Powersports Amplifier with Bass Remote

• 65 watts x 4 channel + 230 watts x 1 channel @ 4 ohm
• 100 watts x 4 channel + 350 watts x 1 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm + 350 watts x 1 channel @ 2 ohm
• Total RMS Power: 750 watts
• Class D 2 ohm Stable 5-Channel Amplifier

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Cerwin-Vega H900.6D

900W RMS Class D HED Series 6 Channel Car Amplifier

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Cerwin-Vega H900.6D

900W RMS Class D HED Series 6 Channel Car Amplifier

• 100 watts x 6 channel @ 4 ohm
• 150 watts x 6 channel @ 2 ohm
• Bridged: 300 watts x 3 channel @ 4 ohm
• Total RMS Power: 900 watts
• Class D 2 ohm Stable 6-Channel Amplifier

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List price $623.99
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Planet Audio MB1200.4D

1200W RMS Class D Planet Pro Series 4 Channel Car Amplifier with Bass Remote

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Planet Audio MB1200.4D

1200W RMS Class D Planet Pro Series 4 Channel Car Amplifier with Bass Remote

• 113 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 D 2 ohm Stable 4-Channel Amplifier

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• 113 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 D 2 ohm Stable 4-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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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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Hifonics A2500.5D Alpha

2500W Peak Class D Alpha Series 5-Channel Car Amplifier (with Bass Remote)

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Hifonics A2500.5D Alpha

2500W Peak Class D Alpha Series 5-Channel Car Amplifier (with Bass Remote)

• 60 watts x 4 channel + 250 watts x 1 channel @ 4 ohm
• 100 watts x 4 channel + 450 watts x 1 channel @ 2 ohm
• 750 watts x 1 channel (Subwoofer) @ 1 ohm
• Total Peak Power: 2500 watts
• Class D 1 ohm Stable 5-Channel-Channel Amplifier

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Hertz HCP 2X

800W Peak (320W RMS) Class AB Hertz Compact Power (HCP) Series 2-Channel Full Range Car Amplifier

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Hertz HCP 2X

800W Peak (320W RMS) Class AB Hertz Compact Power (HCP) Series 2-Channel Full Range Car Amplifier

• 100 watts x 2 channel @ 4 ohm
• 160 watts x 2 channel @ 2 ohm
• Bridged: 320 watts x 1 channel @ 1 ohm
• Total RMS Power: 400 watts
• Class A/B 2 ohm Stable 2-Channel-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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• 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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    FAQ for Multi-channel Amplifiers for Adding Speakers in 2003 S8

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