In this guide
BMW speaker upgrades are among the most effective upgrades you can make to a modern car, because the factory speakers are small, budget parts in a layout that is already well designed. Most BMWs from the last two decades share the same basic speaker positions, so direct-fit replacements simply swap in. Here's how the system works and where to start.
How a BMW sound system is laid out
Most BMW 1, 2, 3, 4 and 5 Series models and many X models from the E, F and G generations use the same arrangement:
- 4 inch (100mm) midrange speakers in the front doors, and often the rear doors or rear deck.
- Tweeters in the door mirror triangles or upper door trims, on most systems.
- 8 inch woofers under the front seats, providing the bass.
- A centre speaker in the dashboard on some models and systems.
Because the woofers are under the seats rather than in the doors, BMWs don't use the 6.5 inch door speakers found in most other cars. That's why BMW upgrades use dedicated parts, rather than standard round speakers.
Which factory system do you have?
This matters more than the model. BMWs come with different audio systems, and each needs a slightly different approach:
- Standard system: speakers driven directly by the head unit. Speaker upgrades make a clear difference; an amplifier makes a bigger one.
- HiFi system (option 676): adds a separate factory amplifier and more speakers. Plug-and-play amplifier and DSP upgrades are designed around this system.
- Harman Kardon (option 688) and Bowers & Wilkins: premium systems with their own amplifiers, different speaker impedances and often more speakers. Upgrades are possible but need parts chosen for that specific system.
Impedance is a common catch: some BMW woofers are 2 ohm and others 4 ohm, which is why direct-fit subwoofers are sold in both versions. Fitting the wrong one can leave the bass weak. If you're not sure which system you have, send us your registration and we'll check.
Stage 1: replace the speakers
Direct-fit speakers bolt into the factory positions and plug into the factory connectors, so nothing is cut. Options include Focal Inside, Audison Prima APBMW, Match UP and Option Audio BM-100 kits. Replacing the front 4 inch speakers and tweeters gives clearer vocals and more detail.
Stage 2: upgrade the underseat woofers
The factory 8 inch underseat woofers are often where BMWs sound weakest. Direct-fit replacements such as the Focal iSUB BMW, Audison Prima APBMW S8, Match UP W8BMW and Morel IP-BMWSUB82 give tighter, deeper bass using the same mounting points. Match the impedance to your system.
Stage 3: add an amplifier and DSP
New speakers on the factory amplifier are an improvement, but they really come alive with proper power and tuning. Plug-and-play amplifiers with built-in DSP, such as the Match UP 8BMW, connect with vehicle-specific harnesses and are tuned to the car. A DSP corrects for the car's cabin and speaker positions, which is what turns a loud system into a good one. Read what is a DSP?
Mini owners too
Many Mini models share BMW's speaker layout, so many of the same direct-fit speakers and subwoofers fit. See Mini speaker upgrades.
Getting it fitted
Shop the full range of BMW speaker upgrades. We fit BMW audio upgrades at our Beeston workshop, and we confirm the right parts for your exact car and sound system before anything is ordered. See our BMW audio upgrades page.
Frequently asked questions
Are BMW speaker upgrades plug and play?
Yes. Direct-fit BMW speakers and subwoofers use the factory mounting points and connectors, so no wires are cut and the car can be returned to standard.
What size speakers are in a BMW?
Most BMW 1 to 5 Series and many X models use 4 inch (100mm) door speakers, tweeters, and 8 inch woofers under the front seats. Exact fitment varies by model and audio system.
Do I need an amplifier for BMW speaker upgrades?
Not to start with. New speakers improve the sound on the factory system, but an amplifier with DSP makes the biggest difference and gets the most from upgraded speakers.
How do I know which BMW sound system I have?
The option code on your car's build sheet shows it: 676 is the HiFi system and 688 is Harman Kardon. Send us your registration and we can check for you.
Are 2 ohm or 4 ohm BMW subwoofers right for my car?
It depends on the factory system. Using the wrong impedance can leave the bass weak, so we confirm which version your car needs before fitting.
Written by the CEN team in Nottingham. Questions? Contact us or call 0115 924 0666.
