Professional Series · Datasheet

Professional Series Ported 12" Enclosure Sundown Audio SA-12 · Single 12" Ported enclosure

Net volume
1.66 Cubic Feet
Tuning
34.5 Hz
Max mounting depth
8.400 Inches (Sundown Audio Spec)
Cutout
11.200 Inches (Sundown Audio Spec)
External dimensions
32.00 Inches W × 16.00 Inches H × 13.50 Inches D
Front baffle
Three 3/4" MDF layers, 2.25" total | Woofer Flush-Mounted In The Outer Layer
Buy at Audio IntensityFactory-direct, ships from Tullahoma
  • Alignment: 1.66 cu ft net vented at 34.5 Hz. F3 29.5 Hz anechoic, 2.56 dB passband ripple
  • Driver: Sundown Audio SA-12 D2, 1500 W RMS, 22.0 mm Xmax, 35.00 Hz Fs
  • Build: Front-firing standard box, 2.25" three-layer baffle with the woofer flush-mounted in the outer layer, Sundown Audio logo acrylic, dado joinery, 32.6 sq in front slot port beside the woofer with one bend along the back wall, port and excursion gated at 1500 W
  • Cabinet: 32.00" W x 16.00" H x 13.50" D, 70 lb, threaded insert kit included

Spec of record

Technical specifications

SeriesProline X Professional
Driver-Specific FitmentSundown Audio SA-12 D2 (D2)
Enclosure TypePorted | Front-Firing Standard Box
External Width32.00 Inches
External Height16.00 Inches
External Depth13.50 Inches
Internal Volume (Gross)2.69 Cubic Feet
Internal Volume (Net After Displacement)1.66 Cubic Feet
Port TypeVertical Slot Beside The Woofer | Front Exit | One 90 Degree Bend Along The Back Wall
Port Geometry2.25 x 14.50 Inches, 32.6 Square Inches, 34.97 Inches Of Path
Port Area32.6 Square Inches
Port Tuning (Fb)34.5 Hz
Port Mouth1/2 In Roundover On All Four Edges, 50.4 Square Inches At The Face
Port Air Velocity24.7 m/s In The Channel, 16.0 m/s At The Mouth, At 1500 W (17.0 m/s Chuff Threshold)
Design Power Basis1500 W RMS (1.2 x The Driver Rating) For Port Velocity And Excursion
Predicted F329.5 Hz (Anechoic)
Passband Ripple2.56 dB (Anechoic)
Subsonic Filter27 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure
Driver Fs35.00 Hz
Driver Qts0.428
Driver Qes / Qms0.525 / 2.308
Driver Vas22.188 Liters / 0.784 Cubic Feet
Driver Sd510.3 Square Centimeters
Driver Mms369.75 g
Driver BL22.99
Driver Re3.4 Ohm
Driver Xmax22mm (One-Way)
Driver Displacement0.18 Cubic Feet (Published by Sundown Audio)
Driver Sensitivity84.5 dB
Driver Power Handling1500 Watts RMS
Driver Overall Diameter12.840 Inches (Sundown Audio Spec)
Mounting Depth Required8.400 Inches (Sundown Audio Spec)
Cutout Diameter11.200 Inches (Sundown Audio Spec)
Flush Mount Recess13.750 Inches In The Outer Layer
MaterialLangboard Elite 3/4" MDF
ConstructionShopSabre CNC / Two Windowed Braces Front To Back Either Side Of The Woofer
JoineryDado Joinery (CNC-Cut), Flat Panels
Front Baffle ConstructionThree 3/4" MDF layers, 2.25" total | Woofer Flush-Mounted In The Outer Layer
Baffle Layers3
AcrylicGlossy Black Sundown Audio Logo Insert, Outer Layer, Standard
Mounting HardwareThreaded Insert Kit Included: 8-12 Inserts, Drill Bit, 2.5 In Allen-Head Screws, Allen Key, Gasket Tape
Voice Coil ConfigurationD2
Terminal CupProline X ABS/Carbon Fiber Composite | Back Panel, Terminal-Cup Side | 12g OFC Pre-Wired
DampingNone - Ships Dry. Polyfill Detunes A Ported Enclosure
Recommended Power1050-1500 Watts RMS (Sundown Audio Rated: 1500W RMS)
Carpet FinishPlush Black
Weight70 lb
ShippingUPS Ground Parcel, Included In The 48 States
Bundle OptionsEnclosure Only (Bring Your Own Sundown Audio SA-12)
Warranty2-Year Limited (Enclosure)
ManufacturedTullahoma, Tennessee, USA

Modelled response

Performance in this enclosure

Net airspace
1.76
cu ft
Tuning
34.0
Hz · Fb
Half power
30.1
Hz · F3, anechoic
Xmax at
4295
W RMS · 27 Hz subsonic
With NO filter
1049
W RMS · unfiltered
Port
15.1
m/s at the mouth · 1250 W

01Is this driver right for a ported box?

Efficiency bandwidth product places the motor before anything else is decided.

EBP = Fs ÷ Qes = 76.7
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 EBP 76.7
Sundown Audio SA-12 v.2 D2 · EBP 76.7
Between 50 and 100 a driver takes either load, and the choice becomes one of priorities rather than of physics. The Sundown Audio SA-12 v.2 D2 reads 76.7. Ported buys output and low-end reach around tuning; sealed buys a shallower rolloff below it. This cabinet takes the first trade.

02What the box does to it

1.76 cu ft net against a 26.3 L Vas, vented at 34.0 Hz.

Fb = 34.0 Hz  ·  F3 = 30.1 Hz  ·  passband ripple 0.59 dB
20 30 50 70 100 150 200 +16 +12 +8 +4 0 −4 −8 −12 −16 −20 −24 −28 FREQUENCY · Hz LEVEL · dB −3 dB Fb 34.0
Sundown Audio SA-12 v.2 D2 · Fb 34.0 Hz, F3 30.1 Hz
Anechoic, before any cabin gain, with the 27 Hz subsonic filter already applied. The vent takes over below 34 Hz and the cone stops doing the work there, which is what holds travel down at the bottom of the passband.

03Ported vs Sealed

No sealed comparison is shown for this driver.

A ported-versus-sealed chart is only worth reading against a sealed box someone would actually build: the one we make for the driver, or the one its maker recommends. Neither exists for the Sundown Audio SA-12 v.2 D2 — we do not build a sealed enclosure for it and Sundown publish no sealed volume for it — so rather than compare this cabinet against itself stuffed and sealed, a box no one would build, the comparison is left out.

04The watts that reach Xmax (in this enclosure)

Travel scales with the square root of power, so there is one wattage that puts the cone exactly on Sundown's published 19.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.

PXmax = 4295 W with a 27 Hz subsonic  ·  1049 W with none  →  the filter is worth 4.1×
20 30 50 70 100 150 200 0 4 8 12 16 20 24 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 19.0 mm 4295 W reaches Xmax here
4295 W · subsonic at 27 Hz, 24 dB/oct1049 W · no subsonic filterXmax 19.0 mm one-way, published
Each trace touches the limit and no further, because each is drawn at the exact power that puts the cone on 19.0 mm. With a 27 Hz subsonic that takes 4295 W, reached first at 26 Hz. Take the filter away and the same cabinet reaches 19.0 mm on 1049 W — the filter is worth 4.1× the safe power. A vent unloads the cone below tuning, so there is nothing holding it once the box stops loading: on a sealed build a subsonic filter is an improvement, here it is required equipment. The unfiltered trace is still rising where this chart stops at 20 Hz, so treat 1049 W as a bound rather than a floor. Every wattage on this page is a MECHANICAL limit, not an electrical one. It is the power at which the cone runs out of linear travel in this cabinet, and nothing more. What the voice coil can dissipate as heat is a separate ceiling set by the driver, not by the box — Sundown rate this one at 1250 W RMS, and that is the number that binds first here: heat stops you before travel does, so treat 1250 W as the ceiling and the travel figures above as headroom. Final wired impedance, amplifier output and how long you hold the level are all electrical questions this graph does not answer.

From the shop floor

Installer's take

I built this box on Sundown's own published numbers for the SA-12, and because the Classic, the v.2 and the v.3 share a basket within two tenths of an inch, one cabinet and one listing covers all three in either coil.

The port here is modeled clean past the v.3's own 1500 watt rating, out to 1697 watts, before mouth velocity becomes the limiting factor rather than the coil; the Classic and the v.2 are rated lower and never get near it.

Wire the D2 coil in series for 4 ohms or parallel for 1 ohm; wire the D4 coil in series for 8 ohms or parallel for 2 ohms. A parallel load under 1 ohm needs an amplifier rated for it.

Sundown Audio publishes no mounting hole locations for the SA-12, so the inserts are not in the baffle when the box arrives. The insert kit is in the box: set the inserts where the woofer's own holes fall, with the drill bit and the 2.5 inch allen-head screws in the kit, and lay the gasket tape before the woofer goes down.

The Performance Optimized wedge is the smaller and cheaper box, and I try it first for every driver. I could not make its port keep up with the SA-12: the calmest port that fits that envelope goes noisy at about 865 watts, under what this coil is rated to take, so I did not sell you that box.

It ships dry. Do not add polyfill to a ported box. Set your subsonic filter at 27 Hz.

Before you order

Questions

Why is this enclosure tuned to 34.5 Hz?

Sundown publishes a Qts of 0.428 for the SA-12 v.3 D2, and it agrees with their own Qes of 0.525 and Qms of 2.308. The gate here is measured at the coil's rated power, 1500 W, and the port stays clean past that rating, modeled to 1697 W before mouth velocity becomes the limiting factor. The v.2 and the Classic are rated lower, 1250 W and 1000 W, so they sit further inside the same port. Ripple across the passband holds at 2.56 dB. Tuning is chosen for in-car response rather than an anechoic curve: a vehicle adds roughly 12 dB per octave below about 45 Hz, and this tuning is where that sum comes out flattest across 25 to 60 Hz.

Why is this a Professional build and not a Performance Optimized box?

Every driver is run through the Performance Optimized wedge and down-fire before this chassis; the Professional box is where a driver lands when that smaller envelope, 30 inches wide and 18 inches deep with a triangular side port, cannot give it what it needs at its rated power. The SA-12 did not clear the port gate there. The calmest wedge port that fits that envelope is 24.7 square inches at 29.0 by 11.62 by 17.27 inches, and its mouth runs 22.4 metres per second at 1500 W against the 17 metres per second line where a port starts to chuff. That port would stay clean to about 865 W. The slot on this box reaches 32.6 square inches and holds the mouth at 16.0 metres per second at 1500 W. An under-ported box does not fail quietly. Air speed at the mouth rises with power; past the chuff line the flow turns turbulent and the port is audible on every note. The turbulence also chokes the port, so the box behaves as if it were tuned higher than it is, loses output near tuning, and lets the cone travel further below tuning than the design allows. This chassis 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, a Sundown Audio logo acrylic, and a port and excursion budget checked at 1500 W. It carries a 2 year warranty against 1.

Threaded inserts or a kit?

Sundown Audio does not publish the mounting hole locations for the SA-12, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: 8 to 12 inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, an allen key and woofer gasket tape. You set the inserts when you mount the woofer; one kit serves one woofer. A dual cabinet ships two kits.

Do I need a subsonic filter?

Yes, at 27 Hz, 24 dB per octave. Below tuning a vented box stops loading the cone and excursion runs away toward DC. With the filter in place this cabinet puts the Sundown Audio SA-12 at 45 percent of its usable travel at 1500 W.

Would a sealed box be better for me?

Below about 23 Hz, yes. The sealed wedge we build for it is louder down there by up to 3.7 dB, because a sealed box rolls off gently into the subsonic region where a vented one falls away steeply once it is under tuning. Above that this alignment is the louder of the two for the same power. The Performance Graphs tab plots this cabinet, 1.66 cubic feet vented at 34.5 Hz, against the 1.00 cu ft sealed wedge we build for this driver (PO 12-S W SA12), so you can see exactly where they cross.

How does the front port work?

It is a vertical slot beside the woofer, the full height of the cavity, 2.25 inches wide and 32.6 square inches. It runs 7.50 inches to the back wall and turns once along it for 21.47 inches; the fold costs about 1.5 Hz and the port is cut for it. The channel runs at 24.7 metres per second at 1500 W, 52 percent of its turbulence limit, and the mouth edges carry a 1/2 inch roundover so the air leaves the face at 16.0 metres per second against the 17 metres per second threshold where a slot starts to chuff.

What does the price cover, and how does it ship?

70 lb, 32.00" W x 16.00" H x 13.50" D external. It ships as a UPS parcel; the price includes shipping in the 48 states. Every Professional cabinet is priced the same way, by its size: this one is 4.00 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 70 lb parcel and checkout adds nothing. Do not add polyfill; it ships dry on purpose.

Is the SA-12 included?

No. This is an enclosure only, cut for the Sundown Audio SA-12 specifically: the 11.200 inch cutout, the 8.400 inch mounting depth allowance and the 1.66 cubic foot alignment all come from Sundown Audio's published parameters. It fits both coil versions; the alignment published here is the D2. Bring your own driver.

Same series, same size

Other Professional Series models