Professional and Performance Optimized

Sundown Audio Subwoofer Boxes and Enclosures

Enclosures cut for Sundown Audio subwoofers, CNC-machined in Tullahoma, Tennessee.

Proline X Micro Series dual 15 inch sealed subwoofer enclosure.

Professional and Performance Optimized

Sundown Audio drivers are built for output, and most of them want a ported cabinet to give it. The enclosures here are machined in Tullahoma, Tennessee and cut to the parameters Sundown publishes for the driver each one names. Where a driver suits the smaller Performance Optimized wedge, that is what it gets; where the port it needs will not fit that envelope, it moves to the Professional chassis. Where Sundown publish a sealed volume that serves the driver, there is a sealed wedge for it too. More Sundown enclosures are being added.

Sundown Audio enclosures in both series, with the port tuned for the driver each cabinet was cut for. More being added.

Cut, assembled and finished in Tullahoma, Tennessee, to the parameters Sundown Audio publishes for each driver.

Driver parameters are taken from Sundown Audio published data. We build enclosures to those figures; we do not currently stock Sundown Audio drivers and make no claim to represent the brand.

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Sealed or Ported for a Sundown Driver

Most of these cabinets are ported, because that is what these drivers are built for. Where Sundown publish a sealed volume that suits the driver, there is a sealed wedge cut to their figure. If you are weighing the two alignments for the same driver, this is the comparison that matters.

General characteristics of the two alignments for the same driver and power.

SealedPorted
Output around tuningLowerHigher, often markedly
Roll-offGentle, about 12 dB per octaveSteep below tuning, about 24 dB per octave
Cabinet sizeSmaller for the same driverLarger: port and alignment both need volume
CharacterTight and dampedLoud and extended around tuning
Best whenSpace is tight or accuracy is the pointYou have the space and want output

Shared across every row: Langboard Elite MDF cut on ShopSabre routers in Tullahoma, Tennessee. Plush black carpet. A Proline X ABS and carbon fibre composite terminal cup with stainless hardware, pre-wired in 12-gauge OFC. Construction method varies by series and is stated on each product page.

Two Series, Chosen by the Port

Every Sundown driver here was run through the Performance Optimized wedge first. That is the smaller cabinet: a fixed envelope with a triangular side port, and it is the one we would rather sell you. A driver moves to the Professional chassis only when that envelope cannot give it what it needs at its rated power, usually because the side port cannot move the air without going audible. Each product page names the gate its driver missed and the power at which the smaller box would have stayed clean.

The port is not a hole in the box. Its length and cross-sectional area together set the tuning frequency, and that frequency is chosen for one specific driver. Change the port and you have a different enclosure rather than a modified one. Around tuning the port radiates alongside the cone and the cabinet produces more output than a sealed box of the same size. Below tuning the port stops loading the cone and output falls away quickly, which is the trade you accept for the headroom above it.

How to Choose

Measure the opening first. The space you have decides more than any specification, and a Professional cabinet is larger than a Performance Optimized wedge by design.

Match the model. Two Sundown drivers of the same nominal size from different lines want different volumes and different tuning. The product page names the model each cabinet was designed around, and the Sundown generations that share a basket are named where one cabinet covers them all.

Read the tuning frequency. Two cabinets of identical net volume tuned a few hertz apart are different products. Pick the tuning that suits the music you actually play.

Then source the driver. We do not currently stock Sundown Audio subwoofers, so these cabinets are cut for a driver you already own or buy elsewhere.

Space, Tuning and the Driver

Airspace first

A ported cabinet needs more volume than a sealed one for the same driver, because the port lives inside it and the alignment needs the room. If your space is tight, a sealed cabinet there will beat a ported one that was shrunk to fit.

Then the tuning

Lower tuning extends deeper and gives up midbass impact; higher tuning does the reverse. Each listing states what its cabinet is tuned to, and that is the number that tells you how it will sound.

Then the driver itself

Ported alignments are less forgiving of a mismatch. The cabinet is cut to a specific Sundown model's published figures, so work from the model number rather than the nominal size.

Port Area Is Not a Detail

A port too small for the excursion you are asking of the driver will make noise, and no amount of tuning afterwards removes it. Our ports are sized for the excursion the driver is rated to, which is why they look large next to a generic box.

We Cut the Box, You Source the Driver

We do not currently stock Sundown Audio subwoofers. These cabinets are built to Sundown's published figures for a driver you already own or buy elsewhere. Nothing about the fit depends on where it came from.

Professional Series Construction

Professional Series is the heavier end of what we build: more baffle, more internal bracing, and port area sized for the excursion the driver is rated to rather than for convenience.

That matters more on a ported cabinet than a sealed one. A port too small for the excursion will make audible noise at volume, and no amount of tuning afterwards removes it.

Heavier build

Professional Series

The Sundown range

More baffle and more internal bracing than our standard driver-matched build. A ported alignment rewards that work more than a sealed one does.

Cut to one driver

Tuned as designed

Port sizing

Stated per cabinet

Length and area cut together to produce a specific tuning, with the area sized for the driver's rated excursion rather than a convenient number.

Ported

Built to order

More on the way

Contact us

Everything is CNC-cut to order in Tullahoma. More Sundown cabinets are being added, and we can quote a configuration that is not listed yet.

Made to order

Baffle thickness and construction method vary by series. Each product page states how that cabinet is built and which Sundown Audio model it was cut for.

Categories

Keep Reading

Supporting guides to help you design, build, and tune your system.

Sundown Audio Subwoofer Box Questions

Which Sundown Audio subwoofers do these boxes fit?

Each cabinet is cut to the published parameters of a specific Sundown Audio model, named on its product page. Match the model number rather than the nominal size, because two Sundown drivers of the same diameter from different lines want different net volumes and different port tuning.

Do you sell Sundown Audio subwoofers?

Not at the moment. We build the enclosure to the figures Sundown publishes and you source the driver. If you already own the subwoofer, that is exactly what these cabinets are for.

Are these ported or sealed?

Mostly ported, because these drivers are built for output and a ported alignment is how you get it. Around the tuning frequency a ported cabinet produces more than a sealed box of the same size. The trade is a larger cabinet and a steeper roll-off below tuning. Where Sundown publish a sealed volume that suits the driver, there is a sealed wedge cut to their figure, and the product page says whose number it is.

What is the difference between the two series?

Every Sundown driver here was run through the Performance Optimized wedge first. That is the smaller cabinet: a fixed envelope with a triangular side port, and it is the one we would rather sell you. A driver moves to the Professional chassis only when that envelope cannot give it what it needs at its rated power, usually because the side port cannot move the air without going audible. Each product page names the gate its driver missed and the power at which the smaller box would have stayed clean. The Professional cabinet is a full-size front-firing box on a 2.25 inch baffle built from three 3/4 inch layers, with the woofer flush-mounted in the outer layer and a slot port the full height of the cavity. The Performance Optimized wedge is a trunk-shaped cabinet on a 1.5 inch double baffle with a triangular side port. Both are cut on our own routers in Tennessee.

What does the tuning frequency actually change?

It sets where the cabinet does its best work. Lower tuning extends deeper and gives up midbass punch; higher tuning hits harder in the midbass and gives up extension. The port length and area produce it, so it is fixed by the cabinet rather than adjustable afterwards.

Can I modify the port to change the tuning?

We do not recommend it. The port is cut to produce a specific tuning for a specific driver, and altering it leaves you with an alignment nobody designed. If you want different tuning, start from a cabinet built for it.

Are you adding more Sundown enclosures?

Yes. More Sundown cabinets are being added. Everything is CNC-cut to order in Tullahoma, Tennessee, so if the size or configuration you need is not listed yet, contact us with the model and we will tell you whether we can build it.

Drivers Built to Match

12 Inch Subwoofers We Do Stock

The drivers below are matched to the enclosures above by Thiele-Small parameters. Buying together guarantees the alignment, port tuning, and damping work the way the engineering intended.

Prodigy Audio 12 inch Subwoofer NB2 Series - Prodigy Subwoofer for car audio systems

Prodigy Audio

Prodigy Audio 12 inch Subwoofer | NB2 Series

$ 150.99 $ 161.99
Image Dynamics ID12 V4 12 inch Subwoofer

Image Dynamics

Image Dynamics ID12 V4 12 inch Subwoofer

$ 159.99
Arc Audio X2V2 12-inch Subwoofer

Arc Audio

Arc Audio X2V2 12" Subwoofer

$ 229.00
Image Dynamics IDQ12 V4 12 inch Subwoofer

Image Dynamics

Image Dynamics IDQ12 V4 12 inch Subwoofer

$ 280.99

View all 12 inch subwoofers | Need a custom build? Contact us

Drivers Built to Match

15 Inch Subwoofers We Do Stock

The drivers below are matched to the enclosures above by Thiele-Small parameters. Buying together guarantees the alignment, port tuning, and damping work the way the engineering intended.

Prodigy Audio 1200 watt 15 inch Subwoofer NB5 Series - Prodigy Subwoofer for car audio systems

Prodigy Audio

Prodigy Audio 1200 watt 15 inch Subwoofer | NB5 Series

$ 434.99 $ 520.99
Image Dynamics IDMAX15 V4 15 inch Subwoofer

Image Dynamics

Image Dynamics IDMAX15 V4 15 inch Subwoofer

$ 679.99

View all 15 inch subwoofers | Need a custom build? Contact us

Amplifiers for the System

Power for Your Subwoofer System

Monoblock amplifiers matched to the power requirements of the drivers these enclosures are built for. Buy the enclosure, match the driver, pick the right amplifier.

Rainbow Audio Dream 0.5K Mono Class D Amplifier

Rainbow

Rainbow Audio Dream 0.5K Mono Class D Amplifier

$ 89.99 $ 399.99
Rainbow Audio SL-M2 2 channel micro amplifier

Rainbow

Rainbow Audio SL-M2 2 channel micro amplifier

$ 98.99 $ 549.99
US Acoustics Lisa 4 Channel Class AB Amplifier 4 x 50w US Acoustics

US Acoustics

US Acoustics Lisa | 4 Channel Class AB Amplifier | 4 x 50w

$ 159.99
US Acoustics Wendy 2 Channel Class AB Amplifier 2 x 75w US Acoustics

US Acoustics

US Acoustics Wendy | 2 Channel Class AB Amplifier | 2 x 75w

$ 159.99

View all car amplifiers | Need a custom build? Contact us

Last updated September 7, 2026