2004-2011 Mazda RX-8 Subwoofer Box Fitment

2004-2011 Mazda RX-8 Single generation (2004-2011) — 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-Seat Sports Car with Freestyle Doors

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 Unconfirmed

Location	trunk, through the trunk opening
Outer bounding box	Vehicle-specific enclosure catalogues; published box footprints are lower bounds on the cavity, not the cavity: NET Audio '2003-2011 Mazda RX8 Sub Box Sealed': 27.625 x 12 x 13.5 in (as printed; axes not labelled), 1.57 cu ft, trunk; "fits up snugly against the back wall"; NET Audio '2003-2011 Mazda RX8 Sub Box Ported': 27.625 x 12 x 13.5 in (as printed; axes not labelled), 1.57 cu ft, trunk; "fits up snugly against the back wall"; SRQ Customs 'RX-8 SINGLE SUBWOOFER ENCLOSURE': 26 x 20 x 12 in (as printed; axes not labelled), 0.75 cu ft of airspace, rear trunk storage shelf; "does require moving the tire kit if equipped (right side only)"; SRQ Customs 'RX-8 WIDE SUBWOOFER ENCLOSURE': 36 x 14 x 10 in (as printed; axes not labelled), 1.5 cu ft for dual woofers, 1.25 for a single 12 in, 0.8 for a single 10 in (airspace; units printed only after the first figure), storage shelf at the back of the trunk; "does require moving the tire kit if equipped". No measured trunk dimensions found.
Known obstructions	SRQ Customs: the shelf boxes "require moving the tire kit if equipped (right side only)". Mounting depth printed by the box makers is 8.5 in (Zenclosures, NET Audio, SRQ Customs) and 10 in (Sound Off Audio).

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 Unconfirmed

Factory speaker size	no maker or Metra source read for the front doors
Adapter bracket needed	unconfirmed

Factory audio integration

Factory amp / premium audio	Mazda, by year. 2004: both versions come with "an AM/FM/CD audio system with six speakers"; the packages include "a BOSE audio system" (the 2004 sheet does not say which package). 2007: Sport has "AM/FM/CD stereo with 6-speakers"; Touring adds "300 watt Bose 9-speaker sound system with AudioPilot noise compensation technology" and an in-dash 6-disc changer; Grand Touring includes everything in Touring. 2011: Sport has "AM/FM/CD stereo with 6-speakers"; Grand Touring and R3 have "300 watt Bose 9-speaker sound system with Centerpoint surround sound and AudioPilot noise compensation". Speaker sizes, positions, the Bose amplifier location and whether any speaker is a subwoofer were not found from a maker page.

Factory amp / premium audio

Mazda, by year. 2004: both versions come with "an AM/FM/CD audio system with six speakers"; the packages include "a BOSE audio system" (the 2004 sheet does not say which package). 2007: Sport has "AM/FM/CD stereo with 6-speakers"; Touring adds "300 watt Bose 9-speaker sound system with AudioPilot noise compensation technology" and an in-dash 6-disc changer; Grand Touring includes everything in Touring. 2011: Sport has "AM/FM/CD stereo with 6-speakers"; Grand Touring and R3 have "300 watt Bose 9-speaker sound system with Centerpoint surround sound and AudioPilot noise compensation". Speaker sizes, positions, the Bose amplifier location and whether any speaker is a subwoofer were not found from a maker page.

Known integration products

no line-output converter or amp interface sourced for the RX-8

Mounting locations

Trunk Solid

trunk, through the trunk opening (below the rear dash)
trunk storage shelf at the back of the trunk

Mazda's spec sheets give 7.6 cu ft of cargo volume (2004 sheet: "EPA Cargo Volume (cu ft)"; 2007 and 2011 sheets: "Cargo Volume, SAE (cubic feet)"). That is a luggage rating, not a box volume. Boxes: Zenclosures 0.75 ft3 per chamber at 8.50 in mounting depth; NET Audio 27.625 x 12 x 13.5 in, 1.57 cu ft at 8.5 in (sealed or ported); SRQ Customs 26 x 20 x 12 in and 36 x 14 x 10 in on the storage shelf (the tire kit, if fitted, has to be moved). Sound Off Audio lists a dual box with 10 in of mounting depth.

Builds and products found for this vehicle

Outside links. Some are commercial products, some are owner builds posted on forums — the label says which. We do not endorse any of them.

Zenclosures (sealed) off-the-shelf
Mazda RX8 Subwoofer Box (SKU RX8). Zenclosures prints the model but no model years. No outside dimensions on the product page. Published volume: 0.75 ft3 per chamber (2 chambers for two subs, 1 for one sub). Mounting depth 8.50 in. Type: sealed. Location: trunk; installed through the trunk opening and slides in below the rear dash. Sub options 1x10, 1x12, 2x8, 2x10, 2x12 in; mounting hole 9 1/8 in for 10 in and 11 1/8 in for 12 in; 0.75 in MDF. Maker note: "fits firmly into place without removing or modifying any part of the car".
Zenclosures (sealed) off-the-shelf
RX8 Subwoofer Box with Amp Rack (SKU rx8ar). Zenclosures prints the model but no model years. No outside dimensions on the product page. Published volume: 0.75 ft3 per chamber (2 chambers for two subs, 1 for one sub). Mounting depth 8.50 in. Type: sealed. Location: trunk; installed through the trunk opening, below the rear dash. Same box with an amp rack: a standard 14 x 10 in plexiglass window, custom window up to about 20 in wide on request. Sub options 1x8 to 2x12 in.
Zenclosures (sealed) off-the-shelf
RX8 Subwoofer Box with Amp Rack - Rotary Symbol Plexiglass (SKU rx8arr). Zenclosures prints the model but no model years. No outside dimensions on the product page. Published volume: 0.75 ft3 per chamber (2 chambers for two subs, 1 for one sub). Mounting depth 8.50 in. Type: sealed. Location: trunk; installed through the trunk opening, below the rear dash. Amp-rack version with a Rotary Symbol plexiglass window. Sub options 1x8 to 2x12 in.
NET Audio (sealed) off-the-shelf
2003-2011 Mazda RX8 Sub Box Sealed (SKU MAZRX8-03). NET Audio states fit years 2003-2011 (the EPA model list has no 2003 RX-8; US sales began with 2004). Published outside dimensions: 27.625 x 12 x 13.5 in (as printed; NET Audio does not label the axes). Published volume: 1.57 cu ft. Mounting depth 8.5 in. Type: sealed. Location: trunk; "fits up snugly against the back wall". Holds "a pair of 8s, 10s or 12s" or a single ported 8 or 10; 3/4 in MDF; 40 lbs.
NET Audio (ported) off-the-shelf
2003-2011 Mazda RX8 Sub Box Ported (SKU MAZRX8-03-P). NET Audio states fit years 2003-2011 (the EPA model list has no 2003 RX-8; US sales began with 2004). Published outside dimensions: 27.625 x 12 x 13.5 in (as printed; NET Audio does not label the axes). Published volume: 1.57 cu ft. Mounting depth 8.5 in. Type: ported (port size, count and length not printed). Location: trunk; "fits up snugly against the back wall". Holds "a pair of 8s or a single 10"; 3/4 in MDF; 45 lbs.
SRQ Customs (1 x 10", other (sealed/ported not stated by the maker)) off-the-shelf
RX-8 SINGLE SUBWOOFER ENCLOSURE. SRQ Customs prints no model years (the page says it "fits all years"). Published outside dimensions: 26 x 20 x 12 in (as printed; SRQ Customs does not label the axes). Published volume: 0.75 cu ft of airspace. Mounting depth 8.5 in. Type: not printed (the page says "Sealed with Fiberglass", which describes the interior finish). Location: rear trunk storage shelf; "does require moving the tire kit if equipped (right side only)". Single 10 in; round or square cutout; left or right side chosen at order.

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SRQ Customs (other (sealed/ported not stated by the maker)) off-the-shelf
RX-8 WIDE SUBWOOFER ENCLOSURE (SKU RX8Dual). SRQ Customs prints no model years (the page says it "fits all years"). Published outside dimensions: 36 x 14 x 10 in (as printed; SRQ Customs does not label the axes). Published volume: 1.5 cu ft for dual woofers, 1.25 for a single 12 in, 0.8 for a single 10 in (airspace; units printed only after the first figure). Mounting depth 8.5 in. Type: not printed (the page says "Interior Sealed with Fiberglass", a finish). Location: storage shelf at the back of the trunk; "does require moving the tire kit if equipped". Dual 10 or dual 12, or a single 10 or 12; room on the back of the box for a small amp; 30 lbs.
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
MAZDA RX8 DUAL SUB BOX (SKU MAZDA RX8 DUAL). Sound Off Audio prints the model but no model years. No outside dimensions on the product page. Published volume: "air space = .8 per sub" (no unit printed). Mounting depth 10 inches. Type: not printed. Location: trunk ("fits in trunk"). Fits "dual 8 or dual 10 subwoofers" (cutouts 7 in for 8s, 9 1/8 for 10s).

Build it for this vehicle

Design a box for this vehicle — Enclosure volume, port tuning, and a see-through render.
Door speaker fitment — No measured door depth on file for this vehicle yet, so there is no fit check to run. The page says how to request one.
See the factory speaker locations — Factory speaker sizes, depths and locations we have researched 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.