Optic Fiber Decoder for Mercedes BMW Porsche Audi - Keeps OEM Audio

In this review the Optic Fiber Decoder from LEXXSON is evaluated as a practical solution for owners who want to retain their original fiber optic amplifier or Harman Kardon/Bose system when replacing the head unit. The bottom line: this decoder is for installers and DIYers who need a straightforward way to decode optical audio lines so the new head unit integrates with the factory speaker system, and it delivers on that promise with mostly plug-and-play installation and wide vehicle coverage.

Key Features

• Vehicle compatibility: Works with a long list of Mercedes Benz, Porsche, BMW and Audi host systems so owners of many German cars can keep factory audio.
• Optical fiber decoding: Decodes TOSLINK-style fiber signals so Harman Kardon and Bose amplifiers with optical inputs continue functioning.
• Plug and play installation: Connects to the head unit can-bus box and fiber connectors up front, avoiding long rear trunk wiring runs.
• Preserves OEM systems: Keeps original navigation, CDC and satellite box integration when the car is compatible, maintaining factory features.
• Compact box design: Small optical fiber box mounts near the head unit and removes the need to route additional long cables.

Who It's For

The decoder is best for owners of Mercedes ML/GL/R, S W221, CLS, SLK, Porsche 911/Cayman/Boxster, BMW E9X/E7X/F0X, Audi 2G/3G host vehicles and VW Touareg 2011-2017 who want to replace their head unit without losing a factory amplifier or optical audio features. It is particularly useful to installers who value reduced labor time since all connections are handled near the dash instead of the trunk.

It is not ideal for vehicles that lack the original navigation, satellite box or CDC, or for users unwilling to verify compatibility first; some cars may also require an additional fiber optic loop adapter, and compatibility checks or messages to the seller are recommended before purchase.

Pros & Cons

Pros

• Keeps OEM Harman Kardon or Bose amplifiers working via optical interface.
• Simplifies installation by avoiding long cable runs and centralizing connections at the head unit.
• Covers a broad range of Mercedes, Porsche, BMW, Audi and VW models so it fits many common upgrades.
• Small, unobtrusive box that integrates with the OEM speaker system.

Cons

• Some models may need an extra optical loop adapter or require confirmation of original navigation/CDC presence for full functionality.
• Connection feedback from some customers is mixed, so careful checking of vehicle host type is advised.

Specifications

Brand	LEXXSON
Compatible vehicles	Mercedes ML/GL/R, S W221, CLS, SLK; Porsche 911/Cayman/Boxster; BMW E9X/E7X/F0X; Audi 2G/3G; VW Touareg 2011-2017
Function	Optic fiber decoder box for factory audio systems
Works with	Harman Kardon and Bose optical amplifier interfaces
Installation	Plug and play, connects to head unit can-bus and fiber connector
Additional parts	May require optical fiber loop adapter for some models

Our Verdict

The LEXXSON Optic Fiber Decoder is a practical and cost-conscious choice for owners who must retain factory optical audio when fitting aftermarket head units. It covers many German models and reduces installation time by keeping connections at the dash, making it good value for installers and informed DIYers who confirm compatibility first.

Frequently Asked Questions

Will this work with Harman Kardon or Bose?
Yes, the decoder is designed to decode optical signals so Harman Kardon and Bose amplifiers with optical interfaces continue to work.

Do I need extra parts?
Some car models require an additional optical fiber loop adapter; check whether your vehicle has the original navigation, satellite box and CDC to avoid issues.

Is installation difficult?
Installation is plug and play in most cases: remove a grey plug to accept fiber wires and connect the fiber optic connector to the head unit can-bus box up front.