Start a project Bespoke car audio
More clarity. More control. More of the music you love—without making your interior look modified.
Custom fabrication / OEM-style finishThe right system, not just more equipment
The best results rarely come from changing one box. Speakers, amplification, acoustics, positioning and tuning all work together—and the vehicle itself is part of the equation.
We design around how you listen, what you drive and what you want to keep. That may mean a carefully chosen factory upgrade or a completely bespoke, digitally tuned system.
Choose your starting point
These are useful ways to frame the conversation. The final specification is designed for your vehicle and priorities.
For drivers who want a clear, worthwhile upgrade without losing space or changing how the car works.
A complete front-end, amplification and DSP solution for a dramatic improvement across every genre.
For the listener who wants exceptional performance, tailored fabrication and total control of the result.
What goes into the result
Select any discipline to see the products, engineering and installation detail behind it.
Hertz installation / bespoke A-pillar buildOur preferred high-end choices
Hertz Mille Legend and Audison Voce II are not interchangeable badges. Mille Legend is our choice when effortless dynamics, detail and a serious two- or three-way front stage lead the brief. Voce II combines natural, controlled sound with excellent installation flexibility. Morel and JL Audio add further speaker and sub-bass options when their design best suits the vehicle, available space and listening priorities. We select the system after assessing the cabin, mounting depth, speaker position, listening level and available DSP channels.
VW Transporter audio · T5 · T5.1 · T6 · T6.1
Start with the result and budget that feel right. We then confirm the van, factory source, seating and available space before turning the guide into an exact specification.
Get my fitted quote ↗
Why Transporters need a joined-up approach
A Transporter is a large, reflective and often noisy cabin. Simply fitting a more expensive speaker leaves much of its potential behind. Our packages combine rigid mounting, acoustic treatment, appropriate amplification, discreet bass and—where specified—proper DSP calibration.
Complete supply-and-install packages
Every price is a supplied, professionally installed and tuned starting price—not a parts-only price. Final cost depends on generation, factory equipment, product choice and fabrication.
The right first step: a cleaner front stage and doors prepared to let the new speakers work properly.
More detail, stronger mid-bass and less door resonance—while retaining the factory appearance.
For everyday driving and touring: a better front stage with compact bass that does not consume the van.
Clear vocals and a fuller low end at sensible listening levels, with the load space kept usable.
The sweet spot: premium speakers, controlled bass and a Forza DSP tune built around the driving position.
More headroom, precise staging and balanced sound at motorway speed without making the dashboard look modified.
A high-end active front stage for the owner who wants scale, control and a far more convincing stereo image.
A wider, more stable soundstage with effortless dynamics and much finer control over every speaker.
Our no-shortcuts Transporter system, designed and fabricated around the cabin rather than a generic parts list.
Reference-level imaging, resolution and impact with a finish that belongs in the vehicle.
These figures are an honest planning guide, not a fixed remote quote. We confirm the vehicle and system before ordering. Equivalent current products may be recommended where they improve fit, availability or performance. Additional rear-cabin audio, extensive soundproofing, head-unit upgrades and unusual previous wiring are quoted separately.
The Unique Integrations method
The packages give you a useful starting point, but the engineering remains vehicle-specific. We leave service access intact, protect the wiring correctly and plan around camper furniture, leisure power and future additions.
A Transporter's large door skins and trim panels can absorb detail and add resonance. We treat the structure, seal the speaker to the cabin and decouple the door card before adding more power.
Audison, Hertz Mille Pro, Voce II or Mille Legend components are selected around listening level, mounting depth and whether the final system will run passive, two-way active or three-way active.
Audison Forza lets us correct timing, level, crossover and tonal balance for the real cabin. It also gives a planned upgrade path instead of replacing the system again later.
The subwoofer should support the front stage without sacrificing the van's job. We consider seat bases, furniture, leisure electrics and load space before choosing an active box or bespoke enclosure.
Keep the factory source—or upgrade it
A DSP system can integrate downstream of the original source, so a new head unit is not automatically required. If you do want Pioneer Apple CarPlay and Android Auto, we can specify the correct fascia, steering-control and vehicle interfaces; compatible T6.1 installations can also retain the factory SOS/eCall function.
Explore Transporter head-unit upgrades ↗A fitted quote starts with the van
WhatsApp the registration or VIN, Transporter generation, a dashboard photo and whether it is a panel van, Kombi, Shuttle or camper. Tell us the package that interests you—or just the result you want—and we will map the right route.
Price my Transporter ↗See all Transporter servicesBMW audio upgrades · Audison Prima & Forza
BMW audio systems look similar from the cabin, but the signal path behind them can be completely different. We identify the factory option first, then build the speaker, harness and DSP package around that exact architecture.
Check my BMW ↗
Why direct-fit matters
Audison's BMW range uses the two three-post frame patterns found across BMW and MINI, shallow neodymium motor assemblies and original-style electrical connections. That lets us improve the system while retaining factory grilles, mounting depth and serviceability.
We do not sell BMW speaker, harness or amplifier kits for self-installation. Every package includes fitment confirmation, installation, configuration and system tuning.
Direct-fit loudspeakers
Exact K4, X4 and S8 versions depend on the chassis, speaker position and system impedance. We confirm the Audison application before ordering.
A 100 mm direct-fit midrange and separate Tetolon-dome tweeter for BMW and MINI factory locations. Audison supplies model-specific cast baskets, tweeter supports, crossover connections and plug-and-play wiring.
Two-way front stage · 4Ω · OEM mounting pointsView manufacturer details ↗A compact 100 mm coaxial option for rear positions—or front locations that cannot accept a separate tweeter. The dedicated basket, fixings and BMW connectors allow a neat replacement without universal adapters.
Rear or restricted locations · 4Ω · Plug and playView manufacturer details ↗Shallow 200 mm woofers designed to replace the BMW units beneath the front seats and work with the existing acoustic enclosures. The 2Ω or 4Ω version is selected around the factory system and amplifier design.
200 mm · Direct-fit frame · 2Ω or 4ΩView manufacturer details ↗Amplifier & RAM integration
BMW used base, Hi-Fi, Harman Kardon, analogue, MOST and later RAM architectures. Some Audison harnesses use physically identical plugs with different pin assignments, so they are not interchangeable.
The under-seat T-harness separates the door midrange and under-seat woofer feeds, then routes them to an Audison DSP amplifier without cutting the original BMW wiring.
For compatible Hi-Fi 676 and low-level Harman Kardon 674 systems, the ReAMP harness can replace the original seven-channel amplifier with an Audison AP bit or AF bit solution.
For RAM-equipped BMWs, ReAMP 3 carries the seven speaker-level RAM outputs into a current Audison Forza amplifier and provides the speaker leads for the front, rear, centre and under-seat channels.
BMW 688 systems can use a separate booster amplifier for the under-seat woofers. Audison's dedicated booster harness preserves the module and vehicle network while routing those channels safely into the Forza upgrade.
RAM-equipped 676 systems normally use 2Ω under-seat woofers. If the Forza design uses bridged channels, the 4Ω APBMW S8-4.2 may be required. We calculate the final load before specifying the amplifier and woofer combination.
The AFBMW BOOSTER 01 is not the route for every 688 layout. Cars with door woofers and a boot subwoofer, including the i4 G26, and vehicles with four under-seat woofers, including the iX, require a different assessment.
Older compatible vehicles may use an Audison ASD bypass harness. On RAM-equipped cars using ReAMP 3, artificial engine sound is handled by vehicle coding instead.
Start with identification
Include the registration or VIN, model year and—if possible—a photograph of the amplifier area. We will confirm the factory audio option, direct-fit speaker set, harness and DSP route before quoting.
Check my BMW on WhatsApp ↗A closer look at the hardware
There is no universal “best” speaker. The right choice depends on the vehicle, the positions we can use, how loudly you listen and whether the system will run passively or fully active.
Dynamic · revealing · effortless
Mille Legend is aimed at the listener who wants more than a louder factory system. Its combination of speed, detail and strong mid-bass gives drums impact, voices presence and complex music room to breathe—even at higher listening levels.
Best suited to Performance and bespoke systems where impact, scale and fine detail all matter.
Natural · controlled · adaptable
Voce II is especially useful when we want audiophile performance without forcing the wrong hardware into an awkward factory position. The range gives us compact and higher-output two-way choices, plus components designed to respond precisely to active DSP tuning.
Best suited to Refined OEM-style upgrades and active systems where integration and tonal balance are priorities.
Why Audison Forza matters
A DSP is only valuable when it is measured and tuned properly. Forza gives us the tools to solve the acoustic and integration problems every vehicle creates, while keeping the finished system simple for you to use.
Many factory systems split the music across several channels and add heavy EQ. Forza can analyse, sum and correct those signals before the new system is tuned, so we are not amplifying the factory system's compromises.
Time alignment compensates for every speaker being a different distance from the listener. Vocals move away from the nearest door and lock into the dashboard, with instruments spread naturally across the cabin.
In an active system, each tweeter, midrange, woofer and subwoofer receives its own channel, crossover, level and phase settings. That improves integration and protects the speakers from frequencies they should not reproduce.
Glass, trim, seating positions and speaker locations create peaks and dips. Careful parametric EQ reduces the distracting problems while preserving dynamics and the character of the chosen speakers.
Channel routing and tuning can be revised if the system grows later. A front-stage upgrade, subwoofer or additional midrange can be integrated properly without throwing away the original design.
What you don't see matters most
A secure mounting, sealed interface, protected wiring and correct crossover setup are what turn good hardware into a good installation. These details live behind the trim—but you hear them every journey.
Ask about your vehicle↗Vehicle-led solutions
We work from the weaknesses and opportunities in each platform—not a universal shopping list.
01JL Audio speakers, amplification and compact bespoke bass can be designed around the Defender cabin—built to perform without taking away the vehicle's usefulness.
JL Audio · Fabrication · Compact sub-bass02Door treatment creates a stronger speaker enclosure, cutting panel resonance and improving mid-bass before tuning even begins.
Door treatment · Component speakers · DSP03Purpose-designed replacements and amplification restore detail and balance while every screen, warning and control remains unchanged.
OEM integration · Under-seat bass · TuningHow it works
Tell us what you drive, what you listen to and what the current system gets wrong.
We inspect the vehicle, set priorities and specify a balanced solution with clear options.
The vehicle is protected, stripped carefully and every component is mounted and wired to our standard.
We measure, listen, calibrate and then show you exactly how to get the best from the finished system.