Upgrading your car audio system in an Audi without a factory premium sound system (such as Bang & Olufsen or BOSE) can be both a rewarding and challenging experience. One of the most common hurdles is the lack of RCA (Cinch) outputs on Audi's OEM head units. This means you can’t simply connect an amplifier via standard low-level RCA cables. Fortunately, there are efficient solutions available that maintain full compatibility and deliver significantly improved sound quality.
In this guide, we'll explore how to install an amplifier using high-level inputs, the benefits of this method, and what else you need to consider for a successful audio upgrade in your Audi vehicle.
Why Audi OEM Head Units Are Different
-
Audi vehicles with standard sound systems typically do not include RCA preamp outputs at the rear of the head unit.
• These systems rely entirely on speaker-level outputs to drive the factory-installed speakers.
• This setup limits traditional amp integration unless you're using a high-level input amplifier or a signal processor.
What Are High-Level Inputs?
-
High-level inputs (also called speaker-level inputs) allow an amplifier to accept the signal from your existing speaker wires.
• The amplifier then processes the signal, often with built-in circuitry that reduces voltage and removes distortion.
• Many modern amplifiers feature dedicated high-level inputs, making them compatible with OEM setups.
Why High-Level Inputs Are Ideal for Audi
-
No RCA output required – ideal for stock Audi head units.
• Preserve OEM functionality – including fader control, parking sensors, and head unit integration.
• Plug-and-play compatible with most speaker wiring, reducing the need for advanced modification.
How to Connect an Amplifier with High-Level Inputs
- Locate Speaker Wires: Identify the front or rear speaker wires from the back of the head unit or from the speaker harnesses.
- Tap the Signal: Use a wiring adapter or speaker wire tap to extract the high-level signal.
- Connect to Amplifier: Wire the tapped speaker signal into the amp’s high-level input terminals or use a compatible plug.
- Set Gain and Filters: Configure gain, low-pass/high-pass filters, and crossover settings according to your speaker configuration.
- Run Power and Ground: Ensure your amplifier has proper power (fused near the battery) and grounding.
Recommended System Configurations
-
Two-Channel Amp – Perfect for boosting front speakers or adding subtle bass via a small subwoofer.
• Four-Channel Amp – Drives front and rear speakers, offering much better clarity and power.
• Five-Channel Amp – Powers four speakers plus one subwoofer for a complete sound system overhaul.
Benefits of Amp Upgrades with OEM Radios
-
Enhanced volume without distortion
• More dynamic range and depth in audio
• Better bass response even from stock speakers
• Compatibility with premium aftermarket speaker kits like the Audi Lautsprecher
Practical Considerations
-
Amp Placement: Under seats, in the trunk, or behind panels to save space.
• Ventilation: Make sure there's airflow to avoid overheating.
• Remote Turn-On: Use signal-sensing or add a relay triggered by the accessory power line.
• Factory Integration: Ensure your new system doesn’t interfere with CAN-BUS signals or other vehicle controls.
Additional Upgrade Options
-
Sound Deadening: Improve clarity and reduce road noise with door and floor insulation.
• MDF Mounting Rings: Use MDF instead of plastic for installing new speakers for better rigidity and sound focus.
• OEM Wiring Adapters: Allow seamless plug-and-play installation without cutting factory wires.
Power Supply and Budget Considerations
-
A basic amplifier and speaker upgrade, including high-level capable amp and all cables, can be done for around €450.
• In contrast, factory or aftermarket premium systems like Bang & Olufsen often cost upwards of €1,500–2,000.
• A well-installed €450 system often provides clearer, more balanced sound than OEM upgrades.
Matching with Audi Speaker Kits
For optimal performance, combine your amplifier upgrade with a high-efficiency speaker kit like those available at Auto-Lautsprecher. Many kits are plug-and-play and include mounting accessories, making installation accessible even for DIYers.
Final Thoughts
Installing an amplifier using high-level inputs in your Audi is one of the most effective ways to boost your sound system without changing the factory head unit. It allows you to maintain the clean look and original functionality of your dashboard while vastly improving sound dynamics, volume, and bass.
With a thoughtful selection of high-efficiency speakers, proper wiring, and MDF installation accessories, you can build a robust audio system that rivals far more expensive factory premium options. Whether you’re an experienced installer or an ambitious hobbyist, this approach offers a reliable and satisfying path to audio excellence.