The Audi A6 C7 3.0 BiTDI 313HP is already an impressive machine, but its active exhaust system takes the driving experience to another level. Using built-in exhaust speakers, this system enhances the sound of the V6 BiTDI engine, delivering a deep, aggressive tone.
Unfortunately, the Kufatec exhaust speakers on my car were blown. After giving them to a so-called “expertd”, which only ruined the new speakers (and he didn’t choose the right ones), I decided to rebuild the active exhaust system myself.
Why Do Active Exhaust Speakers Fail?
Active exhaust systems from brands like Kufatec, Cete, and Maxhaust rely on high-power speakers to generate artificial exhaust notes. Over time, these speakers can fail due to:
🔧 Extreme heat cycles inside the mufflers
🔧 Moisture buildup, leading to corrosion
🔧 Factory speaker design flaws
In my case, the original Kufatec speakers had completely blown, leaving me with a silent exhaust and a small repair job ahead.
Choosing the Right Replacement Speakers
To restore my Audi A6 C7’s active exhaust system, I needed high-quality, waterproof 6.5-inch 2-ohm speakers that could withstand extreme conditions.
After researching, I chose:
✔ Audison AP 6.5 2-Ohm (16.5 cm, 70W RMS) speakers
✔ Water-repellent coating for durability
✔ Additional hydro-isolating spray for extra protection
These speakers were a perfect fit and a major upgrade over the stock ones.
The Rebuild Process
Step 1: Removing the Mufflers
Since the exhaust speakers are housed inside the mufflers, I had to first remove them. This required lifting the car, unbolting the exhaust mounts, and carefully taking off the mufflers.
Step 2: Cutting Open the Speaker Housings
Inside each muffler, the speakers are enclosed in a sealed metal sphere. To access them, I had to:
🔧 Use an angle grinder to carefully cut open the sphere
🔧 Extract the blown speakers
🔧 Inspect for water damage
Step 3: Installing the New Speakers
Once the old speakers were removed, I:
✔ Soldered the new Audison AP 6.5 speakers in place
✔ Sealed the connections with high-temperature silicone
✔ Coated the speakers with hydro-isolating spray for better longevity
To prevent future water damage, I drilled two small holes at the bottom of each sphere, allowing moisture to drain out.
Step 4: Sealing the Speaker Housings
I didn’t want to repeat the mistakes of the so-called “specialist” who previously worked on my car. He welded the spheres shut, ruining a perfectly good pair of speakers.
Instead, I:
✔ Used silicone and a metal bracket to secure the sphere halves together
✔ Left them accessible for future speaker replacements
✔ Reinstalled the mufflers and tested the system
Results: 6 Months Later
At the time of writing this, my active exhaust system has been working flawlessly for six months. The Audison speakers deliver deep, rich sound without distortion, and the drain holes prevent water buildup, ensuring longevity.
Would I Do It Again?
Absolutely. This DIY exhaust speaker rebuild saved me hundreds of euros, and the final result is better than stock. If you have an Audi A6 C7 3.0 BiTDI, SQ5, or any vehicle with an active exhaust, replacing the speakers is a great alternative to buying a whole new system.
Looking for waterproof speakers? Check the ones we have in our site.
