You don’t have to be an audio expert to know when a track played in your Bimmer sounds like a banger or isn’t quite there yet…
But can you tell what the audio system’s quality will be before even getting your new car?
If you want to make sure the BMW sound system you’re putting your hands on is spot on, or at least OK, you gotta learn some basics about the 4 standard BMW audio systems. And since there’s always room for improvement, we’ll show you how you can upgrade each to make it a true gem.
Behind the Audio-Scenes – BMW iDrive System
Now, before we get into detail describing the available BMW audio setups, let’s talk iDrive. After all, it’s the infotainment system that determines what hardware is used throughout the interior of the car and how well its potential is employed.
What we cover in this article mostly applies to bimmers equipped with iDrive 6 and iDrive 7 & 8 systems. This is because there are some important differences between both of these and they can be found on the vehicles of the same generation. Even despite configuring your car with the same options for the respective iDrive version, you’d be getting significantly different audio-related electronics.
That being said, let’s go over all standard BMW audio systems and compare their iDrive variations.
BMW Factory Audio Setups
Let’s see if you recall having one of these – the 4 most common factory BMW sound systems.
The Base (Stereo) system, as the name suggests, is the most basic audio kit you can find in your BMW. If you come from Canada or the US and own a 2012+ car, you’re very unlikely to have one in your BMW, and would have the HiFi system as the standard option instead. Chip shortage exceptions apply.
Since Base in its iDrive 6 version is composed of only 6 BMW speakers (4 midrange speakers and 2 underseat woofers) and no tweeters or dedicated BMW amplifier whatsoever, even the slightest music fan will find the tunes coming out of it quite dull.
For the iDrive 7 Base setup the audio quality improves a bit, since all of the speakers are powered by the Receiver Audio Module (RAM), which functions as both the receiver and amplifier, but the amount of speakers is the same.
Thanks to the DAC and DSP (Digital to Analog Converter & Digital Signal Processing) applied by the RAM, the signal is converted from digital to analog, resulting in 6 dedicated speaker channels. And making the audio sound better.
Hi-Fi System (S676A)
A level above, and at the same time a noticeable improvement over the Base stereo audio system, is BMW’s HiFi (S676A) option. You can recognize it by 9 BMW speakers – including 2 tweeters and an additional midrange in the dashboard (some BMWs won’t have any center channel speakers or will only have a midrange without a tweeter, others might also have tweeters in the rear) – as well as an 8-channel BMW amplifier fitted in the trunk (with only 7 channels used to power the speakers).
It’s a considerable step ahead of Base, since HiFi’s BMW amplifier located in the trunk has a lot more power than the head unit’s one, and is able to provide a dedicated amp channel for each BMW speaker or speaker pair. What you’re getting out of that are louder sounds with less distortion, plus more capable woofers (2 Ohm impedance) delivering lower bass and clearer tunes at higher volumes. Overall – decent speakers and good quality performance… Nonetheless, they could still use some low end thump driven by a BMW amplifier upgrade.
Similarly to Base system, the iDrive 7 version of Hi-Fi also gets the RAM with its DSP, resulting in 7 channels of analog signal being sent to all speakers individually.
Harman Kardon (S674A)
Now, here comes the tricky part with the mix up of Harman Kardon naming conventions.
The Harman Kardon Hi-Fi system (S674A) is another small step above the respectable HiFi system. Let us say that again and stress it – it’s only a small level up since its amp features a moderate power advantage with the same amount of channels as the Hi-Fi system (S676A), and varies just a little in the number of speakers (each midrange is paired with a tweeter) and coding in the head unit.
You may have been under the impression that what you call a Harman Kardon must carry the aura of the household sound system, with its almost unpleasantly loud volume levels. But, in fact, the Harman Kardon Hi-Fi system (S674A) is a more modest sibling of the Harman Kardon surround sound system (S688A) and was created for smaller chassis vehicles. That, of course, came to the disappointment of many i3 or 2-Series owners who expected to be swept off their feet by the heaps of power, but ended up with a system which merely resembles the promised quality known from BMW’s big SUV’s and sedans.
Harman Kardon 674 no longer exists as an option in iDrive 7 & 8 BMWs.
Top HiFi (Harman Kardon S688A)
Finally, the cream of the crop of the factory standard options, Harman Kardon surround sound system (S688A) finds itself on the top of the pile. Those of you who feature it in your BMWs can easily notice that out of all 4 systems, it comes with the most plentiful amount of speakers – usually 16 – including 2 very powerful (8 Ohm) woofers, and 7 mid-ranges along with 7 tweeters placed all over the vehicle. Again, compared to other BMW amplifiers, the Harman Kardon one is without a doubt the largest and heaviest-hitting, with its 10 channels and fiber optic cable, which transfers your audio signal digitally allowing for further customization.
Can You Upgrade BMW Speakers?
As luck would have it, even if you miss out on the mighty Harman Kardon (S688A), you don’t need to settle for your vehicle’s stock BMW speakers. With BimmerTech’s high-end BMW speaker upgrades, we can replace the entire speaker kit from whatever factory audio option you have – even the abundant HK.
If you ask us what distinguishes their Alpha One Speakers from other stock kits, it’s primarily the combination of solid materials with a premium build, designed to closely match the factory equivalent. Covering these, BimmerTech audio engineers tailored their BMW speaker upgrades to deliver the most rich, well-balanced and clear sound, while also being a spot on fit for BMWs of all ages, shapes and sizes.
Need Something More? BMW Amplifier
However, a precisely engineered set of BMW aftermarket speakers is only 50% of the way to achieve a powerful sound. For a complete knock-out punch, you need a finely tuned BMW sound system upgrade.
BimmerTech’s BMW amplifier with its fully custom-tuned 64-bit DSP, 1140W max output, 30-band graphic EQ, and numerous sound-shaping filters, will surely hit all the right notes and tones straight from the get go. Thanks to the DSP tuning, the amp will come adjusted to the cabin of your vehicle, as well as to your favourite genres and style of listening.
And if that’s not enough, BimmerTech sound engineers will tweak your audio system after the installation, to make sure it resonates specifically with you.
BMW Amplifier or Speaker Upgrade? What to Buy First?
Well, that will depend on which system you have from the factory. If it’s Harman Kardon Hi-Fi (S674A) or HiFi (S676A) you should definitely start off by upgrading the BMW amplifier – for that, BimmerTech’s Alpha One Amplifier will do wonders.
Since both of these stock solutions have quite decent sets of speakers, by simply adding an upgraded amp to your BMW audio system, you’ll reap the benefits of more power, optimized stereo imaging, smoother frequency response, and, most importantly – DSP tuning files optimized for your chassis and musical preferences.
Beware though: going Alpha One once might leave you wanting to elevate the system even further. If that’s the case, BMW aftermarket speakers from BimmerTech will give you the deeper bass and more balanced sound you’ll be looking for.
If Base is what you have installed from the factory, upgrading both the BMW speakers and the entire BMW sound system all at once is your best solution.
Due to the fact that the basic factory system doesn’t feature tweeters to begin with, the peak frequency here is 12kHz while a good audio system should roll off at 20kHz. Moreover, because the factory Base woofers are only capable of producing thin sounding bass, no matter how much you try to EQ them, the sound will neither come out richer nor deeper. To resolve this issue, you’d be best off getting the set of aforementioned Alpha One audio upgrades.
Do you want to get that extra bit of crispiness, punch, and clarity from your Harman Kardon surround sound (S688A) system? Replacing the HK speakers for the Alpha Ones will do the trick and make your audio quality unrivalled. Check out how they differ from each other: