BMW M235i Convertible 2015

BMW 676 HiFi Sound System Upgrade

The medium-range series of the BMW sound systems on all models up to 2020, the 676 HiFi, is also the one that is the easiest to upgrade. For this purpose, we use a solution that has been developed and produced in Germany by Audiotec Fischer in a combination with another German brand MUSWAY and the Italian STEG.

Original Setup:

676 Hifi sound system factory amplifier,
3-way splits in the front: 1″ tweeter, 4″ midrange, 8″ underseat woofer,
2x midrange 4″ speaker in the rear
a mid-range dashboard centre speaker

Mediocre sound quality, not enough bass, low volume output

New Setup:

MATCH UP 7BMW – PnP DSP amplifier
MUSWAY CSB4.2C BMW – Direct fit speakers – front
MUSWAY CSB42X BMW – Direct fit speakers – rear
STEG BZ40D – 1x Dashboard speaker – centre
STEG BM8 – Drop-in underseat subwoofers
STP Aero – Premium soundproofing system

Chris works in the sound industry and he is a singer himself and he was looking for a solution to enhance his BMW with a better sound system. After the initial meeting, he had a chance to select between several different speaker brands as he listened to how they performed one by one at our studio. Check the video to see his feedback about the new system.

We have replaced the factory amplifier for MATCH UP 7BMW that fits directly in the car, the matching harness comes with the amplifier. It was followed with the same style replacement of the speakers and the underseat subwoofers. All the parts we used have been made to fit BMW so there was no need for any modifications other than undoing a few bolts and putting them all back. All 4 car doors have been soundproofed and after the whole setup was active and ready, we tuned the sound in and the job was done.

For the dashboard centre speaker and underseat subwoofers, we used the STEG. STEG is a high-quality Italian brand that has great components with a very flat frequency response to begging with. They sound very natural and pleasant to the ear, perfect for everyday use. For the front and rear speakers, we chose the brand MUSWAY which gives a clearer and punchier sound. That way the sound is more likely to cut through the wind noise when the roof it down.

Since this car came without tweeters to begin with, we supplied the matching OEM tweeter domes for this vehicle from a BMW dealer from a higher series with the Harman Kardon sound system. We only used the housings and populated them with our tweeters of the brand MUSWAY.



This setup is suitable for all BMW models with the 676 HiFi system all up to the year 2020. Please contact us to check the compatibility with your vehicle.


Dynamic sound, clear tones and a great bass frequency response.

The stage has been precisely tuned up with the sound image oriented for the driver’s seat. That way it’s a much more enjoyable experience to drive the car around.

Installation time: 1 day

Customers Reviews & Comments

Installation Photos

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