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2025 Audi S4

Universal gear includes car amplifiers, subs, and other products that do not install in a specific location or require fitment to integrate with a vehicle.

Universal-Fit Audio for 2025 Audi S4

When thinking of universal gear, we consider products like a car amp that gives more power to your speakers or subs, cell phone chargers, equalizers and sound processors, rear-seat entertainment and video monitors, as well as dash cameras.

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NVX XCAP10H (TRUE 10 FARAD CAPACITANCE)

True 10 Farad Stiffening Hybrid Capacitor with Digital Display and Built-in Distribution Block

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True 10 Farad Stiffening Hybrid Capacitor with Digital Display and Built-in Distribution Block

• For High-Powered systems
• Bright Blue LED Voltage Display
• Improves Bass Response (SPL)

15% off an NVX XCAP10H w/ Select Amp Kits
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• For High-Powered systems
• Bright Blue LED Voltage Display
• Improves Bass Response (SPL)

Tru Spec Dual 12in P (1460YX)

Empty Dual 12" Vented Prefabricated Enclosure for Sundown SA 12" Subwoofers

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Empty Dual 12" Vented Prefabricated Enclosure for Sundown SA 12" Subwoofers

• 12" Dual Ported Subwoofer Enclosure
• 3/4" Medium Density Fiberboard (MDF) construction
• Total box volume: 3.50 cubic feet
• Compatible for Sundown SA 12V2 subwoofers (Sold separately)

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List price $299.99
-22% $234.99

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JBL JBLSUBBPACCKITAM

BassPro Go Vehicle Installation Kit

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BassPro Go Vehicle Installation Kit

• BassPro Go Vehicle Installation Kit
• Designed for installing a JBL BassPro Go powered subwoofer in another vehicle
• Vehicle mounting bracket, hardware and harnesses included

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List price $139.95
-21% $109.95

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• BassPro Go Vehicle Installation Kit
• Designed for installing a JBL BassPro Go powered subwoofer in another vehicle
• Vehicle mounting bracket, hardware and harnesses included

Single 10" Sealed MDF Subwoofer Enclosure (Belva MDFS10)

10-inch Sealed Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (0.77 cu ft airspace 10SQTC)

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10-inch Sealed Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (0.77 cu ft airspace 10SQTC)

• 0.77 cu ft Sealed Enclosure
• 3/4" Medium Density Fiberboard Construction
• Durable Black Carpeting
• Pre-Lined with Poly-Fil
• Gold Speaker Terminals

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List price $99.99
-40% $59.99

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Sundown Audio GT-R1 (GT1R8)

100W RMS 2" 8-ohm Pro Audio Super Tweeter (S-GT1R8)

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100W RMS 2" 8-ohm Pro Audio Super Tweeter (S-GT1R8)

• Super Tweeter
• 100 watts RMS Each
• 8 ohm Impedance

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List price $47.99
-17% $39.99

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• Super Tweeter
• 100 watts RMS Each
• 8 ohm Impedance

NVX NDA12001

2400W Peak (1200W RMS) Class D N-Series Monoblock Car Amplifier with Bass Remote

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2400W Peak (1200W RMS) Class D N-Series Monoblock Car Amplifier with Bass Remote

• 500 watts x 1 channel @ 4 ohm
• 850 watts x 1 channel @ 2 ohm
• 1200 watts x 1 channel @ 1 ohm
• Total RMS Power: 1200 watts
• Class D 1 ohm Stable Monoblock Amplifier

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List price $239.99
-29% $169.99

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NVX XSBI500

500-Amp Microprocessor-Controlled Dual Sensing Smart Battery Isolator and Relay (Handles up to 700-Amp Surge)

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500-Amp Microprocessor-Controlled Dual Sensing Smart Battery Isolator and Relay (Handles up to 700-Amp Surge)

• 500-Amp continuous / 700-Amp surge
• Ideal for car stereo systems and mobile electronics
• Prevents the main starter battery from draining
• 10V to 16.5V DC operating range

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• 500-Amp continuous / 700-Amp surge
• Ideal for car stereo systems and mobile electronics
• Prevents the main starter battery from draining
• 10V to 16.5V DC operating range

Belva BLPCAM2

License Plate Mounted Waterproof Rearview Backup Camera with Built in Night Vision

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License Plate Mounted Waterproof Rearview Backup Camera with Built in Night Vision

• Universal Rear View Backup Camera
• Mounting Style: Full License Plate Frame
• Resolution: 720 x 480 
• Waterproof: Yes
• Nightvision: Infrared LED's

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• Universal Rear View Backup Camera
• Mounting Style: Full License Plate Frame
• Resolution: 720 x 480 
• Waterproof: Yes
• Nightvision: Infrared LED's

Limited time!

Kicker HS10 (51HS10)

180W RMS Single Loaded 10" Hideaway Series 4-ohms Amplified Subwoofer Enclosure with Bass Remote

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180W RMS Single Loaded 10" Hideaway Series 4-ohms Amplified Subwoofer Enclosure with Bass Remote

• 10" Amplified Loaded Subwoofer System
• 180 watts RMS
• Built-In Class D Amplifier
• Variable Bass Boost
• Speaker-Level Inputs
• Wired Remote Bass Level Control

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• 10" Amplified Loaded Subwoofer System
• 180 watts RMS
• Built-In Class D Amplifier
• Variable Bass Boost
• Speaker-Level Inputs
• Wired Remote Bass Level Control

NVX VBTERM2

Round Push Style Outer Design Terminal Cups With Chrome-Plated Contacts

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Round Push Style Outer Design Terminal Cups With Chrome-Plated Contacts

• Universal Round Chrome-plated Terminal Cup for Speaker & Subwoofer boxes
• Chrome-plated contacts for optimal signal transfer
• Screw binding posts for a tight secure connection
• Positive (Red) and negative (Black) indicators to ensure proper wiring
• Easy to install and use

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• Universal Round Chrome-plated Terminal Cup for Speaker & Subwoofer boxes
• Chrome-plated contacts for optimal signal transfer
• Screw binding posts for a tight secure connection
• Positive (Red) and negative (Black) indicators to ensure proper wiring
• Easy to install and use

JL Audio 12W6v3-D4

600W RMS 12" W6v3 Series Dual 4-ohm Car Subwoofer

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600W RMS 12" W6v3 Series Dual 4-ohm Car Subwoofer

• RMS Power: 600 watts
• Impedance: Dual 4 ohm
• Mineral-Filled Polypropylene Cone
• Butyl Rubber Surround
• Mount depth: 7.52"
• Sensitivity: 85.4 dB

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NVX VCW122 Version 3 (VCW122v3)

2400W Peak (1200W RMS) 12" VC-Series v3 Dual 2-ohm Car Subwoofer

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2400W Peak (1200W RMS) 12" VC-Series v3 Dual 2-ohm Car Subwoofer

• Peak Power: 2400 watts
• RMS Power: 1200 watts
• Impedance: Dual 2 ohm
• Carbon Fiber Enhanced Non-Pressed Paper Cone
• Custom High Roll Foam Surround with black nylon stitching
• Mount depth: 7.02"
• Sensitivity: 85 dB (1W/1m)

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Viper 7756V

2-Way LCD Replacement Remote Control

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2-Way LCD Replacement Remote Control

• 2-Way Replacement Remote
• 5-Button Transmitter
• 1 Mile Range
• Color: Black

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• 2-Way Replacement Remote
• 5-Button Transmitter
• 1 Mile Range
• Color: Black

Stinger SGP35

500 Amp Relay and Isolator

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500 Amp Relay and Isolator

• Prevents Primary Battery Discharge
• Maximum Current Transfer
• Ideal for 2nd Audio Battery Isolation from Vehicle Systems
• 500A Constant/ 900A Peak

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• Prevents Primary Battery Discharge
• Maximum Current Transfer
• Ideal for 2nd Audio Battery Isolation from Vehicle Systems
• 500A Constant/ 900A Peak

Escort Coiled SmartCord Blue

Direct Power Coiled SmartCord with Blue LED Lights and Built-In Mute Button

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Direct Power Coiled SmartCord with Blue LED Lights and Built-In Mute Button

• Direct Power Smartcord for Escort Radar Detectors
• Blue LED Light Notifies You of Alerts
• Built-in Mute Button to Silence Audio Alerts
• Works with all current generation escort windshield mounted detectors

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• Direct Power Smartcord for Escort Radar Detectors
• Blue LED Light Notifies You of Alerts
• Built-in Mute Button to Silence Audio Alerts
• Works with all current generation escort windshield mounted detectors

JL Audio 10TW3-D4

400W RMS 10" TW3 Series Dual 4-ohm Shallow Subwoofer

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400W RMS 10" TW3 Series Dual 4-ohm Shallow Subwoofer

• RMS Power: 400 watts
• Polymer/Mica Composite Cone
• Rubber Surround
• Impedance: Dual 4 ohm
• Mount depth: 3.25"
• Sensitivity: 82.10 dB

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$519.99

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NVX VCW82 Version 3 (VCW82v3)

1300W Peak (650W RMS) 8" VC-Series v3 Dual 2-ohm Car Subwoofer

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1300W Peak (650W RMS) 8" VC-Series v3 Dual 2-ohm Car Subwoofer

• Peak Power: 1300 watts
• RMS Power: 650 watts
• Impedance: Dual 2 ohm
• Carbon Fiber Enhanced Non-Pressed Paper Cone
• High Roll Foam Surround with black nylon stitching
• Mount depth: 5.31"
• Sensitivity: 83 dB (1W/1m)

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Alpine KCX-CAM1

Composite RCA to Direct Camera Adaptor for Alpine Stereos

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Composite RCA to Direct Camera Adaptor for Alpine Stereos

• Composite RCA to direct camera adaptor
• Compatible with all Alpine stereos with direct camera input
• Ideal for adding any aftermarket camera
• Plug and play, no cutting or splicing required

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$19.95

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• Composite RCA to direct camera adaptor
• Compatible with all Alpine stereos with direct camera input
• Ideal for adding any aftermarket camera
• Plug and play, no cutting or splicing required

AudioControl MATRIX PLUS

6-Channel Line Driver with Optional Level Control

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6-Channel Line Driver with Optional Level Control


• Active 6-Channel Line Driver
• Increase pre-amp signal levels up to 9.5 volts RMS
• Matches the volume levels between different sources
• Two channels of input can drive all six outputs
• Each output can drive up to seven amplifiers

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• Active 6-Channel Line Driver
• Increase pre-amp signal levels up to 9.5 volts RMS
• Matches the volume levels between different sources
• Two channels of input can drive all six outputs
• Each output can drive up to seven amplifiers

Single 12" Vented MDF Subwoofer Enclosure (Belva 1SV12B)

12-inch Vented Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.8 cu ft airspace 1SV12B)

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12-inch Vented Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.8 cu ft airspace 1SV12B)

• Single 12" Vented MDF Enclosure
• Holds one 12" subwoofer
• 3/4 MDF (Medium Density Fiberboard) Construction
• Durable black carpeting
• Gold Terminals
• Internal Box Volume: 1.8 cubic ft.

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    FAQ for Universal-Fit Audio & Electronics in 2025 S4

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    A: Yes this page includes all the best Universal-Fit Audio & Electronics that work in your S4.

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