What we researched for this specific generation: where an enclosure actually fits, what the factory speakers are, how the factory audio is wired, and which real builds and commercial products exist for it. Confidence badges say how well each figure is sourced — this is research, not manufacturer spec.
Body styles covered: 4-Door Sedan
These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.
| Location | recess in trunk side behind factory amp panel, or behind rear seats |
|---|---|
| Outer bounding box | 15 liters (~0.53 ft3) — fit-box product used as proxy |
| Known obstructions | A factory amp panel is present at the trunk-side recess and should be worked around, not necessarily replaced |
| Usable volume estimate | 0.53 ft³ |
Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.
| Subwoofers | 1x8" small sealed, behind rear seats |
|---|---|
| Box type | sealed |
| Location | behind rear seats, unused space |
| Subwoofers | 1x10" sealed, 15L (~0.53 ft3) |
|---|---|
| Box type | sealed |
| Location | trunk-side recess behind factory amp panel |
Sizes and depths below are what research turned up for this generation. Confirm against your own vehicle before cutting or ordering — trim levels vary.
| Factory speaker size | 6.5" — handles midrange punch, midrange role confirmed (not full-range) since the tweeter is dash-mounted, not door-mounted |
|---|---|
| Known obstructions | None specifically documented |
| Adapter bracket needed | unconfirmed |
| Tweeter | n/a in the door — real, confirmed the factory tweeter (Vifa XT25SC90 on non-B&O systems) is DASH-CORNER mounted, firing up into the windshield, with a factory 10kHz crossover rolloff inside the amp. On Bang & Olufsen-equipped trims, the dash layout keeps the outer positions for tweeters with a smaller center-dash position for the midrange — same general dash-mounted architecture, genuinely different from the sibling Q5's mirror-quadrant/A-pillar tweeter location. |
| Midrange | IN THE DOOR — the 6.5" door driver serves the midrange role given the dash-mounted tweeter handles high frequencies separately. |
| Factory speaker size | 5.25" |
|---|---|
| Known obstructions | None specifically documented |
| Adapter bracket needed | unconfirmed |
| Tweeter | n/a — tweeter is dash-corner mounted, front only |
| Midrange | n/a — 5.25" rear door driver role (midrange vs. full-range) not independently confirmed |
| Factory amp / premium audio | Bang & Olufsen available as Audi's premium partnership on equipped trims — same Harman-family ownership note applies as BMW/other luxury brands |
|---|---|
| Adding subs without a head-unit swap | Confirmed straightforward via the trunk-side recess or behind-seat approaches; a factory amp panel is present and should be worked around, not necessarily replaced |
| Head unit | No replacement needed |
Real specific product: 'fit-box' enclosure, 10" driver, 15 liters (~0.53 ft3). Real builder approaches found: fiberglass boxes shaped to fit the recess in the trunk side behind the factory amplifier panel, or small sealed boxes tucked into unused space behind the rear seats — both genuinely low-impact approaches rather than a standalone box eating trunk floor space.
Outside links. Some are commercial products, some are owner builds posted on forums — the label says which. We do not endorse any of them.
Each link opens the tool with this vehicle already selected.
Measure your own vehicle. Trim levels, factory subwoofer options, and mid-generation changes all move these numbers, and a box cut to a researched figure that does not match your truck is wasted wood. Where a badge reads Unconfirmed, treat the value as a starting point for your own measurement, not as an answer.