2016-2020 Cadillac CT6 Single generation (Omega platform) — subwoofer box fitment

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

Where a box actually fits

These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.

Trunk Likely

Locationtrunk
Outer bounding boxReal total trunk figure: 15.8 ft3. Real installer guidance (not a single measured box, but a repeated real recommendation): up to ~14 ft3 of that can be used for a custom box without sacrificing trunk functionality; up to 4 ft3 ported is workable for 2x12" in a non-SPL build.
Known obstructionsNone specifically documented
Usable volume estimate4 ft³

Starting points

Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.

Budget

SubwoofersPowered sub, sized from your own trunk measurements
Box typepowered enclosure
Locationtrunk / rear cargo area

Enthusiast

Subwoofers1x10" or 1x12" sealed, built to measurements taken from your own car — no published envelope exists
Box typesealed
Locationtrunk / rear cargo area

Competition

SubwoofersNot sizeable from this page. No measured cargo envelope is published for this vehicle; measure first
Box typecustom
Locationtrunk / rear cargo area

Door speaker fitment

Sizes and depths below are what research turned up for this generation. Confirm against your own vehicle before cutting or ordering — trim levels vary.

Front doors Likely

Factory speaker size4" (100mm) ON BOSE PANARAY CARS — and that is not a typo. Bose's own press material for the Panaray system states 4" (100mm) speakers in each front and rear door, and that only ONE speaker in the entire 34-speaker system is larger than 100mm (the rear deck woofer). MANUFACTURER TIER, but PANARAY-SPECIFIC: base and mid-tier CT6 door sizes are NOT documented anywhere reached.
Known obstructionsA 4" door driver in a flagship sedan is counter-intuitive and worth pausing on before ordering: Panaray achieves its output through speaker COUNT and placement rather than cone area, so there is no large door woofer to upgrade. Anyone planning a conventional 6-1/2" component swap on a Panaray car is planning around a door that was never built for one. No removal procedure exists — no Research Garage article.
Adapter bracket neededunconfirmed — no bracket requirement documented for this vehicle
TweeterInstrument panel — centre and corners. PANARAY cars only.
Midrangen/a — Panaray's architecture does not map cleanly onto a woofer/midrange/tweeter breakdown, and Bose does not describe it that way.

Rear doors Likely

Factory speaker size4" (100mm) in each rear door on PANARAY cars (MANUFACTURER TIER — Bose press material). Base-system rear door size is not documented.
Known obstructionsNot documented in any reachable source.
Adapter bracket neededunconfirmed

Factory audio integration

Factory amp / premium audioBOSE PANARAY IS THE HEADLINE SYSTEM — 34 speakers driven by FOUR amplifiers, introduced on the 2016 CT6 as a first-of-its-kind system. It is also the fitment gate for the integration part below, which requires Bose. CRITICAL SCOPE LIMIT ON THIS PAGE: every speaker size here is Panaray-specific, taken from Bose's own press material. The CT6 also shipped with lesser systems, and NONE of their speaker sizes are documented in any source reached.
Adding subs without a head-unit swapAssumed yes, but not documented for this vehicle. With no measured cargo envelope and no removal procedures published, treat any build here as requiring your own measurements first.
Head unitNo replacement needed

Known integration products

Mounting locations

Trunk Likely

NO CRUTCHFIELD RESEARCH GARAGE ARTICLE EXISTS FOR THIS CAR — verified against the complete 296-entry index re-harvested 2026-08-04. That matters because the Research Garage is the only source that publishes measured cargo bounding boxes, which is why this entry has no raw_cavity_envelope and why its speaker data comes from weaker sources than the rest of the catalog. Measure your own car before cutting wood. No measured cargo dimensions are published for this vehicle in any source reached, and no vehicle-specific commercial enclosure with published volume was found either. Measure before building.

Build it for this vehicle

Each link opens the tool with this vehicle already selected.

Before you cut anything

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.