BMW 4 Series F33 Harman Kardon | Upgrade to Premium Sound System

BMW 4 Series Audio Upgrade | Harman/Kardon to Premium

Model: BMW 435i Coupé F33 2014 with Harman/Kardon Sound System

Although the Harman Kardon BMW sound system was the top of the range offered for F30/F33 models for a time, it still had its limitations. One of these was the fact that the top cover of the factory amplifier was full of vents, which is not a great choice for a convertible – any water leaking in was able to go straight into the electronic parts of the sound system, which wreaks all sorts of havoc.

This is exactly why this customer reached out to us – it seems their convertible had decided to take on water, essentially frying their Harman Kardon stereo system. The team at Soundtech was more than happy to take a look and also quote on a BMW Coupe speaker upgrade.

Original Setup:

The BMW’s original sound system included:

    • 16-speaker Harman/Kardon sound system running on a 25Mbit optical network
BMW 4 Series F33 Harman Kardon | Upgrade to Premium Sound System BMW 4 Series F33 Harman Kardon
BMW 435i F30 Harman/Kardon Audio Upgrade

Whilst the Harman Kardon system installed by BMW is a relatively good one, it’s still one of those ‘one-size-fits-all’ approach systems that provide half decent sound at the best of times. It’s acceptable for most drivers, but the real music aficionados are never going to be satisfied. The best way to improve the sound is to replace pretty much everything.

The original amplifier came to us damaged, as water had gotten into it when the customer’s convertible started leaking. As replacing the original amp with the exact same one could get costly, not to mention would only provide the same old results, it was decided that we would fix the issue with a much better outcome instead. And all for a similar budget.

New Setup:

    • Optical to Toslink converter
    • MATCH UP 7BMW DSP amplifier
    • STEG 4″ component speakers front
    • STEG 4″ component speakers rear
    • STEG 4″ component speakers center
    • STEG 8″ under seats subwoofers
    • Parcel shelf speakers temporarily disconnected
    • Custom-tuned sound stage and more power
    • Installers trained and certified by Audiotec Fischer

We installed an ‘Optical to Toslink’ converter, then fed the signal to a 7 channel DSP amplifier that powers the entire car. This combination was fitted instead of the factory amp, conveniently using the same space it inhabited.

We excluded the two rear parcel shelf speakers from the setup, which were left inactive to cut down the cost a little but could have been powered by either an additional 2 channel amplifier or by a MATCH UP 10DSP (so that one device drives the whole system). Not having these speakers connected has no impact on the sound quality of the system at all – in fact, it sounds so much better than it did previously with all of the sub-par speakers connected and working.

We performed a car speaker replacement while we were at it, replacing every other speaker in the vehicle – including the centre one – and tuned the whole thing up.

The actual car sound system tuning process can take up to 3 hours to complete, as this is performed according to the particular vehicle we’re working on as well as the customer’s specifications. We hook the system up to complex PC software and run through the whole thing manually to ensure we’re satisfied with the sound produced.

Even though MATCH amplifiers already feature a hole-less top cover (making them more resistant to water), we also created a protective shield with a drip-foam stripe going all the way around it that we fitted above the amp – just in case the convertible decided to start leaking again. The whole thing came together really well and we loved how it looked.

Why Plug and Play?:

We work exclusively with Plug and Play connections at Soundtech, as this ensures that the vehicle’s original sound system is not altered in any shape or form. Instead, all of the new components are hooked up using special plugs and adaptors.

This allows the car to be returned to its original factory settings with ease – and with zero traces of our installation left behind. If the customer wants to sell their BMW 4 Series and keep the upgraded sound system, for example, or if they want to have an even more advanced system installed down the line, they will be able to do so without issue.


    • Plug and Play only, no cutting
    • More bass
    • Stealth installation
    • Clarity and precision of sound achieved
    • Just one of those things your car secretly begs for

The customer was very happy with the new sound system we provided and was particularly appreciative of the extra steps taken to protect it against potential future water ingress. Car speaker replacement and car sound system tuning are just some of those things that your vehicle secretly begs for, so we were more than happy to be of assistance.

We specialise in what is known as ‘stealth installation’, which simply means that all components are hidden away in the body of the vehicle and that no wiring is cut. The whole idea is that you’d never guess any work had been done – it will appear as if this is the way that the vehicle always looked.

Our team has also been factory trained and licensed by Audiotec Fischer, the world’s leading car audio manufacturer, so you can rest assured that your vehicle is in the best hands possible. In fact, our Founder, Honza, has visited the German-based company’s factory on a number of occasions to ensure he’s up to date with all their innovative techniques.

The team at Soundtech can effortlessly complete BMW Coupe speaker upgrades and sound system installation in around 1 business day, ensuring that you’ll be back on the road and pumping out sweet tunes in no time.

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If you own a BMW 4 Series and are unhappy with the sound quality produced by its stereo system, be sure to get in touch with us on (02) 9055 7400 or to see how we can help.

Installation Photos