How to Build a Complete Sound Upgrade in the Peugeot 308 II
If your Peugeot 308 II speakers sound distorted, weak or completely dead, you are not alone. Many owners experience deteriorating sound quality after a few years because the factory door speakers are not designed for long-term performance. A proper upgrade not only restores clarity but transforms the entire listening experience. The detailed German guide Peugeot 308 II Lautsprecher nachrüsten – Einbau Tipps provides a practical foundation for the mechanical work – in this article we go further and explain how to design a complete, future-proof sound system for your Peugeot 308 II.
The Peugeot 308 II (model years 2013–2021) is particularly suitable for DIY upgrades because all factory speakers are mounted inside the door panels. There are no dashboard bass units or A-pillar midranges to complicate the installation. With basic tools and careful handling, even hobby mechanics can replace and upgrade the system successfully.
Why you should never replace only one door speaker
Replacing a single broken speaker may look like a quick fix, but it creates an uneven soundstage. Speakers always have different efficiency ratings (measured in dB/W/m). When you mix brands or models on one side only, one door will play noticeably louder. The result is an unbalanced stereo image that feels as if the balance control is permanently shifted.
Always replace speakers in pairs and ideally use the same brand and model series front and rear.
Speaker layout in the Peugeot 308 II
- Front doors: 165 mm 2-way component system with external tweeters located near the door handle
- Rear doors: 165 mm coaxial or component speakers depending on trim level
- Factory impedance: 4 Ohm
- Mounting depth: sufficient for most aftermarket speakers without modification
Step-by-step replacement overview
- Remove the side and bottom screws of the door panel.
- Carefully pry off the inner door handle cover and the outer grip trim.
- Remove the window switch unit and disconnect the wiring.
- Lift off the complete door panel.
- Unscrew the three speaker mounting screws.
- Press the locking tab on the plug and disconnect the speaker.
- Install the new speaker and reconnect the plug.
- Before reassembling, check that the tweeter cable is connected correctly.
- Reinstall the panel in reverse order.
Door damping – the hidden performance upgrade
One of the most underestimated improvements is door damping. Applying vibration-absorbing mats behind the speaker and on the outer door skin reduces resonance dramatically. Benefits include:
- tighter bass response
- cleaner midrange
- less door rattling at higher volumes
- improved overall sound pressure
This step alone often makes factory radios sound twice as good.
Passive subwoofer system vs. active subwoofer
| Feature | Passive subwoofer + amplifier | Active subwoofer |
|---|---|---|
| Installation effort | Higher – requires amplifier wiring | Very easy – all-in-one unit |
| Upgrade flexibility | Maximum – any enclosure and driver size | Limited to built-in speaker |
| Sound quality | Highest potential output | Very good for daily listening |
| Cost | Medium to high | Low to medium |
| Space requirement | Usually boot mounted | Under seat or compact boot unit |
Using the factory radio vs. aftermarket head unit
The original Peugeot 308 II radio does not provide RCA outputs, but you can still connect amplifiers using high-level inputs or a line-output-converter.
If you replace the factory unit, most aftermarket radios include:
- clean RCA pre-outs
- separate subwoofer control
- adjustable crossovers
- time alignment and EQ features
This opens far more tuning options and allows much cleaner bass integration.
Three recommended sound upgrade setups
1) Budget daily setup
- 165 mm door speakers front and rear
- Door damping
- Compact active subwoofer under passenger seat
2) Balanced sound system
- High-efficiency component speakers front and rear
- Small 4-channel amplifier connected to factory radio
- Passive subwoofer in sealed boot enclosure
3) Premium sound build
- Aftermarket head unit with RCA outputs
- 4-channel amplifier for door speakers
- Mono amplifier and custom subwoofer enclosure in the boot
Crossover settings and tuning basics
- Door speakers: High-pass filter at 80–100 Hz
- Subwoofer: Low-pass filter at 80–90 Hz
- Always keep all speakers at 4 Ohm impedance for safe amplifier operation
- Ensure correct phase alignment to avoid bass cancellation
Where to find the right speakers
For a complete selection of tested systems, visit Peugeot 308 Lautsprecher kaufen on auto-lautsprecher.eu – a specialised platform for DIY enthusiasts that provides free installation guides and in-depth technical advice.
Final thoughts
The Peugeot 308 II is one of the most upgrade-friendly vehicles in its class. With all speakers located in the doors and generous mounting space, even complex sound systems are achievable without cutting or drilling. Whether you go for a simple replacement or a premium system with amplifiers and subwoofer, the result will transform every drive into a high-fidelity experience.
