A customer from Falls Church, Virginia came to WSS Westminster Speed & Sound recently to upgrade the audio system in his 2011 BMW 328xi. He opted to do it in two stages. The 1st stage is described in detail in this post. The second stage was designed to give him very detailed, accurate bass, and allow more volume from the stereo system.
We installed an Arc Audio KS500.1mini amplifier in the driver’s side rear corner of the trunk. This amplifier will provide 500 watts of clean power to the subwoofer. Signal for this unit was gotten from the JL Cleansweep that we installed in Stage 1.
A Kicker KX2 crossover was also installed to allow us to bandpass the musical frequencies going to the woofers under the front seat. In Stage 1 the front woofers were allowed to play down as low as possible so we could extract all the bass they were able to reproduce. Now that we have a dedicated subwoofer we repurpose the woofers under the front seats as mid-bass drivers. They now bridge the gap musically between the subwoofer in the trunk and the 4” midranges installed in the front doors. Bandpassing the woofers also allows them to play louder while reproducing crystal clear audio.
For a subwoofer we chose a JL Audio 10W3. It is a very musical subwoofer that works in a small enclosure, yet has great output potential. We installed a custom made fiberglass enclosure that tucks into the rear passenger side of the trunk, and as you can see from the pictures, looks like a factory part. The enclosure is designed to be removable in the event the battery needs to be accessed.
Stinger Roadkill was applied to the rear deck in the vehicle to eliminate rattling of the rear deck. This generation BMW is a very solid car so it does not need much damping material in the trunk unless a very large system is being installed. The system was then tuned for the new gear.
Stage 2 BMW Bass Upgrade Completes The Package
The sound quality of the 2nd Stage was fabulous. The low end was now extremely tight and detailed and it played these frequencies with ease. The front sound stage in the vehicle married beautifully with the subwoofer, allowing concert level volume with studio sound quality.
When we did the first demo with the customer he started grinning from ear to ear. He absolutely loved the sound quality, volume level, and factory fit and finish. And that was music to our ears. If you own a BMW and would like the sound system to match the performance of the rest of the vehicle, call us, email us, or even better, stop in. We will custom design a system for your individual needs.
Check out this video to see why you should consider WSS Westminster Speed & Sound when upgrading the car audio system in your BMW: