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, 2-Door Coupe (2015-2019)
These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.
| Location | trunk |
|---|---|
| Outer bounding box | Real, multiple named commercial products, not one outlier: dual-12" sealed, 11.75" mounting depth, 3/4"+1/2" MDF, ~35 lbs. Dual-10" alternative: 8.5" mounting depth. |
| Known obstructions | Real, useful detail: enclosure is sized to leave room for an amp between the box and the back seat. |
| Usable volume estimate | 2.2 ft³ |
Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.
| Subwoofers | 1x10" or 1x12" sealed, sized from your own trunk measurements |
|---|---|
| Box type | sealed |
| Location | trunk |
| Subwoofers | 2x10" at 1.75 ft3 with 8.5" mounting depth — a commercially available vehicle-specific spec for this car, so it is known to fit |
|---|---|
| Box type | sealed |
| Location | trunk |
| Subwoofers | 2x12" at 2.2 ft3 with 11.75" mounting depth — the largest configuration with published vehicle-specific specs. Anything beyond that is unguided, because no measured trunk envelope exists |
|---|---|
| Box type | sealed |
| Location | trunk |
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 | 6-1/2" — CORROBORATED THREE INDEPENDENT WAYS, after an initial draft of this entry recorded it as unresolved. (1) A dedicated speaker-size reference (allspeakersize.com) lists the 2013-2016 ATS front door panel as 6.5" midbass/full-range. (2) The Metra 82-3006 adapter, listed by multiple retailers for the 2013-2019 ATS, adapts the 6"-to-6-3/4" family into this location — consistent. (3) Crutchfield's own per-vehicle shopping page recommends a 6-1/2" for this car. THE OUTLIER: one Cadillac Owners Forum poster describes the door speakers as 8", which does not fit the other three and is treated as mistaken. A separate forum report of fitting 5-1/4" components is not a contradiction — 5-1/4" drops into a 6-1/2" opening with a bracket. NOTE THE YEAR COVERAGE: the size chart runs 2013-2016, so 2017-2019 is inferred from the unchanged generation rather than directly sourced. Still worth measuring before you buy. |
|---|---|
| Known obstructions | The Metra 82-3006 doubles as a SPACER/EXTENDER for speakers with large magnets, specifically to stop them hitting inside the door — which is a strong hint that depth clearance behind the factory location is tight. The bracket itself measures 8.75" x 7.25" x 2.00", so it adds roughly 2" of standoff. A real installation reported on the Cadillac Owners Forum used Infinity REF-6522ix speakers with the 82-3006 mount. |
| Adapter bracket needed | Yes — Metra 82-3006 is the named part, and it is what makes 6" through 6-3/4" speakers fit this location |
| Tweeter | A-pillar / windshield pillar. Multiple forum posts describe A-pillar-mounted tweeters and name them as a commonly replaced item, and one notes they add crispness at low volume. Location is consistently reported; size is not. |
| Midrange | n/a — no separate door midrange documented in any reachable source |
| Factory speaker size | 6-1/2" — two sources agree. A dedicated speaker-size reference (allspeakersize.com) lists the 2013-2016 ATS rear door panel as 6.5" midbass/full-range, and Crutchfield's per-vehicle shopping page recommends a 6-1/2" 2-way as a rear speaker for this car. Same size front and rear on this platform. Year coverage of the chart is 2013-2016; 2017-2019 is inferred from the unchanged generation. |
|---|---|
| Known obstructions | Not documented in any reachable source. |
| Adapter bracket needed | unconfirmed |
| Factory amp / premium audio | BOSE IS THE PREMIUM TIER AND IT IS THE FITMENT GATE FOR THE INTEGRATION PART BELOW. A 10-speaker Bose system was optional on this car (reported for 2014), alongside a base system. This is the one area where the ATS has a genuinely solid, manufacturer-published source: PAC's own application guide lists the 2015 ATS as compatible with its AmpPRO subwoofer interface WITH Bose, and explicitly NOT compatible without Bose. So establishing whether a given car has Bose is the first thing to do, and it determines whether the named part below applies at all. |
|---|---|
| Adding subs without a head-unit swap | Yes on Bose cars, via the PAC interface below. On non-Bose cars no vehicle-specific part is documented, so a universal high-level-input line-output converter is the fallback. |
| Head unit | No replacement needed |
NO MEASURED TRUNK ENVELOPE EXISTS FOR THIS CAR — Crutchfield has no Research Garage article for the ATS, and its Research Garage is the only source that publishes measured cargo bounding boxes. WHAT IS AVAILABLE INSTEAD IS ARGUABLY MORE USEFUL TO A BUILDER: real vehicle-specific enclosures are sold for the 2013-2017 ATS with published volumes and mounting depths — a DUAL 12" at 2.2 ft3 with 11.75" of mounting depth, and a DUAL 10" at 1.75 ft3 with 8.5" of mounting depth. Both are described as leaving room to mount an amplifier between the back of the box and the rear seat. Treat those as proof of what physically fits rather than as a bounding box, and measure your own trunk before cutting wood. DO NOT use Cadillac's published SAE trunk volume (a ~10.4 cu ft figure appears in manufacturer literature for the sedan) as an enclosure figure — SAE cargo volume is measured with a luggage-block method and has no relationship to a usable rectangular box envelope.
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.