UK car audio comparison

Best BMW Car Audio Upgrade Products
in 2026.

A practical comparison of vehicle-specific car-audio upgrade products, with the fitting and compatibility details checked before ordering.

Prices and stock should be checked on the retailer page before purchase.

Our approach. We compare the specifications shown on the retailer product pages and explain who each model suits. This is not a hands-on test.

Our pick

BLAM RELAX BL-BM100NC BMW and Mini 4" 2ohm 2-Way Coaxial Car Audio Speakers (PAIR)

A component option for making a factory system clearer without changing the whole car.

Check price

Full specifications

Our picks compared

This table includes every verified specification available for the products in this roundup. Check the retailer page for the latest price, stock and fitment details.

Product	Price	Availability	Brand	Model	Product Type	Speaker Design	Subwoofer Design	Size	Listed Power	Full specifications
BLAM RELAX BL-BM100NC BMW and Mini 4" 2ohm 2-Way Coaxial Car Audio Speakers (PAIR)	£129.99	In stock	BLAM	BL-BM100NC	Car Speakers	Component	Not listed	Not listed	100W	Impedance: 2 Ω Freq Type: Coaxial Speakers
Focal ICBMW-100L 4" 100mm Inside BMW 2-Way Coaxial (Pair)	£159.00	In stock	Focal	ICBMW-100L	Car Speakers	Coaxial	Not listed	Not listed	Not listed	Type: Coaxial Speakers
Focal ISUBBMW-4 Underseat 4 Ohm Subwoofer upgrade for BMW Vehicles	£199.00	In stock	Focal	ISUB BMW-4	Underseat Car Subwoofers	Not listed	Active	Not listed	Not listed	Power Detail: 4 Ohm Size Detail: 10 inch Type: speakerupgrade
BLAM RELAX BL-BM200WN BMW 200mm (8 inch) Extra-Flat Underseat Car Subwoofers (PAIR)	£219.00	In stock	BLAM	BL-BM200WN	Underseat Car Subwoofers	Component	Not listed	Not listed	200W	Impedance: 2 Ω Freq
Focal ISBMW-100 - Custom Fit 4" 2-Way Component Speakers 80W for BMW	£249.99	In stock	Focal	ISBMW100	Car Speakers	Component	Not listed	Not listed	80W	Type: Speakers
Phoenix Gold ZDSB200S 8 Inch 150W Subwoofer Kit for BMW	£349.99	In stock	Phoenix Gold	ZDSB200S	Subwoofer	Not listed	Not listed	8 inch	150W	All listed fields are shown

Product notes

What each pick is best at

Best overall speaker upgrade

BLAM RELAX BL-BM100NC BMW and Mini 4" 2ohm 2-Way Coaxial Car Audio Speakers (PAIR)

A component option for making a factory system clearer without changing the whole car.

What we like

Lowest listed price in this comparison at £129.99, £29.01 below Focal ICBMW-100L.
The only pick here listing 100W power, giving it a clear difference from the other 5 options.
The component layout gives more control over tweeter placement than the coaxial alternatives.

What we don't like

Unlike some alternatives, the listing does not show a comparable design figure, so matching it to the rest of the system takes more checking.
Separate tweeter placement and crossover wiring make it more involved to fit than the coaxial picks.

Price	£129.99
Availability	In stock
Listed Power	100W
Model	BL-BM100NC
Speaker Design	Component
Brand	BLAM
Impedance	2 Ω Freq
Product Type	Car Speakers
Type	Coaxial Speakers

Check CarAudioCentre.co.uk

Best for clearer front sound

Focal ICBMW-100L 4" 100mm Inside BMW 2-Way Coaxial (Pair)

A coaxial option for making a factory system clearer without changing the whole car.

What we like

At £159.00, it costs £29.01 more than BLAM BL-BM100NC, so the extra spend is tied to the specification and fitment choice.
The only pick here listing Coaxial design, giving it a clear difference from the other 5 options.
The coaxial layout keeps the drivers together, which is usually the simpler replacement route for a factory door or shelf speaker.

What we don't like

It is £29.01 above the cheapest pick, so the higher price depends on whether the distinct Coaxial design suits the installation.
The fixed coaxial layout offers less placement flexibility than a component set, and the speaker size and depth still need measuring.

Price	£159.00
Availability	In stock
Model	ICBMW-100L
Speaker Design	Coaxial
Brand	Focal
Product Type	Car Speakers
Type	Coaxial Speakers

Check CarAudioCentre.co.uk

Best for boot-based systems

Focal ISUBBMW-4 Underseat 4 Ohm Subwoofer upgrade for BMW Vehicles

A active subwoofer choice for adding more weight to the system.

What we like

At £199.00, it costs £69.01 more than BLAM BL-BM100NC, so the extra spend is tied to the specification and fitment choice.
The only pick here listing Active design, giving it a clear difference from the other 5 options.
Its active design includes amplification in the product, unlike passive options that need a separate amp.

What we don't like

It is £69.01 above the cheapest pick, so the higher price depends on whether the distinct Active design suits the installation.
The enclosure and underseat or boot dimensions still need checking, even where the product is described as compact.

Price	£199.00
Availability	In stock
Model	ISUB BMW-4
Subwoofer Design	Active
Brand	Focal
Power Detail	4 Ohm
Product Type	Underseat Car Subwoofers
Size Detail	10 inch
Type	speakerupgrade

Check CarAudioCentre.co.uk

Best for factory stereos

BLAM RELAX BL-BM200WN BMW 200mm (8 inch) Extra-Flat Underseat Car Subwoofers (PAIR)

A bass subwoofer choice for adding more weight to the system.

What we like

At £219.00, it costs £89.01 more than BLAM BL-BM100NC, so the extra spend is tied to the specification and fitment choice.
The only pick here listing 200W power, giving it a clear difference from the other 5 options.
The product type gives a clear starting point for deciding between a compact bass upgrade and a separate amplifier setup.

What we don't like

It is £89.01 above the cheapest pick, so the higher price depends on whether the distinct 200W power suits the installation.
The enclosure and underseat or boot dimensions still need checking, even where the product is described as compact.

Price	£219.00
Availability	In stock
Listed Power	200W
Model	BL-BM200WN
Speaker Design	Component
Brand	BLAM
Impedance	2 Ω Freq
Product Type	Underseat Car Subwoofers

Check CarAudioCentre.co.uk

Best high-output option

Focal ISBMW-100 - Custom Fit 4" 2-Way Component Speakers 80W for BMW

A component option for making a factory system clearer without changing the whole car.

What we like

At £249.99, it costs £120.00 more than BLAM BL-BM100NC, so the extra spend is tied to the specification and fitment choice.
The only pick here listing 80W power, giving it a clear difference from the other 5 options.
The component layout gives more control over tweeter placement than the coaxial alternatives.

What we don't like

It is £120.00 above the cheapest pick, so the higher price depends on whether the distinct 80W power suits the installation.
Separate tweeter placement and crossover wiring make it more involved to fit than the coaxial picks.

Price	£249.99
Availability	In stock
Listed Power	80W
Model	ISBMW100
Speaker Design	Component
Brand	Focal
Product Type	Car Speakers
Type	Speakers

Check CarAudioCentre.co.uk

Best for flexible installation

Phoenix Gold ZDSB200S 8 Inch 150W Subwoofer Kit for BMW

A 8-inch bass subwoofer choice for adding more weight to the system.

What we like

At £349.99, it costs £220.00 more than BLAM BL-BM100NC, so the extra spend is tied to the specification and fitment choice.
The only pick here listing 8-inch size, giving it a clear difference from the other 5 options.
The product type gives a clear starting point for deciding between a compact bass upgrade and a separate amplifier setup.

What we don't like

It is £220.00 above the cheapest pick, so the higher price depends on whether the distinct 8-inch size suits the installation.
The enclosure and underseat or boot dimensions still need checking, even where the product is described as compact.

Price	£349.99
Availability	In stock
Listed Power	150W
Model	ZDSB200S
Size	8 inch
Brand	Phoenix Gold
Product Type	Subwoofer

Check CarAudioCentre.co.uk

Buying guide

What to check before ordering

Confirm the exact make, model, generation and year before ordering. Some upgrades are vehicle-specific speakers or DSP kits, while others still need a fascia, loom, aerial adapter or factory-amplifier interface.

Use the model number as the final reference. Retailer images and prices can change, and vehicle fitment should be confirmed for the exact make, model and year.

Best BMW Car Audio Upgrade Productsin 2026.

BLAM RELAX BL-BM100NC BMW and Mini 4" 2ohm 2-Way Coaxial Car Audio Speakers (PAIR)

Our picks compared

What each pick is best at

BLAM RELAX BL-BM100NC BMW and Mini 4" 2ohm 2-Way Coaxial Car Audio Speakers (PAIR)

What we like

What we don't like

Focal ICBMW-100L 4" 100mm Inside BMW 2-Way Coaxial (Pair)

What we like

What we don't like

Focal ISUBBMW-4 Underseat 4 Ohm Subwoofer upgrade for BMW Vehicles

What we like

What we don't like

BLAM RELAX BL-BM200WN BMW 200mm (8 inch) Extra-Flat Underseat Car Subwoofers (PAIR)

What we like

What we don't like

Focal ISBMW-100 - Custom Fit 4" 2-Way Component Speakers 80W for BMW

What we like

What we don't like

Phoenix Gold ZDSB200S 8 Inch 150W Subwoofer Kit for BMW

What we like

What we don't like

What to check before ordering

Best BMW Car Audio Upgrade Products
in 2026.