Performance Optimized · Datasheet

Performance Optimized Down Fire Ported 10" Enclosure DD Audio SL610 · Single 10" Ported enclosure

Net volume
1.35 Cubic Feet
Tuning
35.5 Hz
Max mounting depth
3.976 Inches (DD Audio Spec)
Cutout
9.252 Inches (DD Audio Spec)
External dimensions
31 Inches W × 7.75 Inches H × 16.00 Inches D
Front baffle
Down Firing - Driver Fires Toward Floor
Buy at Audio IntensityFactory-direct, ships from Tullahoma
  • Alignment: 1.35 cu ft net vented at 35.5 Hz. F3 30.3 Hz anechoic, 3.29 dB passband ripple
  • Driver: DD Audio SL610 D2 or D4, 600 W RMS, 19.0 mm Xmax, 29.00 Hz Fs
  • Build: Proline X V-groove and dado joinery, L-wrap slot port with a faceted 90 degree bend, double-layer 1.5" baffle, side-mounted terminal cup
  • Cabinet: 31" W x 16.00" D x 7.75" H measured in down fire position, 9.50" tall installed on its feet, square corners, ships dry

Spec of record

Technical specifications

SeriesProline X Performance Optimized Down Fire
Driver-Specific FitmentDD Audio SL610 D2 or D4
Enclosure TypePorted | Down Fire Geometry | Floor-Coupled
Baffle ConfigurationDown Firing - Driver Fires Toward Floor
External Width31 Inches
External Depth16.00 Inches
External Height7.75 Inches (Cabinet Only)
FeetIncluded - 1.75 Inch Standoff, Required For Down Fire Operation
Installed Height9.50 Inches (7.75 Cabinet Plus 1.75 Feet) - MEASURE AGAINST THIS, NOT THE CABINET HEIGHT
Dimension ReferenceAll External Dimensions Measured In Down Fire Position
Internal Volume (Gross)1.49 Cubic Feet
Internal Volume (Net After Displacement)1.35 Cubic Feet
Port TypeL-Wrap Slot | One Folded Wall | Single Faceted 90 Degree Bend
Port Tuning (Fb)35.5 Hz
Port Channel3.75 x 6.25 Inches (23.4 Square Inches)
Port Path Length29.21 Inches (Centreline)
Port Mouth Area30.9 Square Inches (3.50 Inch Corner Chamfer)
Port Air Velocity16.0 m/s At Tuning (17.0 m/s Chuff Threshold)
Predicted F330.3 Hz (Anechoic)
Passband Ripple3.29 dB (Anechoic)
Subsonic Filter28 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure
Driver Fs29.00 Hz
Driver Qts0.372
Driver Qes / Qms0.393 / 6.878
Driver Vas26.769 Liters / 0.945 Cubic Feet
Driver Sd350.8 Square Centimeters
Driver Xmax19mm (One-Way)
Driver Displacement0.03 Cubic Feet (Published by DD Audio)
Driver Sensitivity84.0 dB
Driver Power Handling600 Watts RMS
Driver Overall Diameter10.600 Inches (DD Audio Spec)
Mounting Depth Required3.976 Inches (DD Audio Spec)
Cutout Diameter9.252 Inches (DD Audio Spec)
Woofer Ring11.500 Inch OD, Bonded Under The Baffle In A Machined Recess
MaterialLangboard Elite 3/4" MDF
ConstructionShopSabre CNC / Windowed Brace Between Cutout And Port Terminus
JoineryV-Groove and Dado (CNC-Cut)
Front Baffle ConstructionDouble-Layer 1.5" MDF | Outer Layer Flush Recess, Driver Mounts To Inner Layer
Corner ProfileSquare (Down Fire Series Standard)
Mounting Hardware8 x #8-32 Hurricane Nuts Fitted (16 Positions Cut For Driver Orientation) | Stainless Steel Machine Screws Included
Terminal CupProline X ABS/Carbon Fiber Composite | Side Mounted | 12g OFC Pre-Wired
DampingNone - Ships Dry. Polyfill Detunes A Ported Enclosure
Recommended Power420-600 Watts RMS (DD Audio Rated: 600W RMS)
Carpet FinishPlush Black
Bundle OptionsEnclosure Only (Bring Your Own DD Audio SL610)
Warranty1-Year Limited (Enclosure)
ManufacturedTullahoma, Tennessee, USA

Modelled response

Performance in this enclosure

Net airspace
1.35
cu ft
Tuning
35.5
Hz · Fb
Half power
30.3
Hz · F3, anechoic
Xmax at
3097
W RMS · 28 Hz subsonic
With NO filter
597
W RMS · unfiltered
Port
16.0
m/s at the mouth

01Is this driver right for a ported box?

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

EBP = Fs ÷ Qes = 73.8
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 EBP 73.8
DD Audio SL610 · EBP 73.8
Between 50 and 100 a driver takes either load, and the choice becomes one of priorities rather than of physics. The DD Audio SL610 reads 73.8. 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

1.35 cu ft net against a 26.8 L Vas, vented at 35.5 Hz.

Fb = 35.5 Hz  ·  F3 = 30.3 Hz  ·  passband ripple 3.29 dB
20 30 50 70 100 150 200 +6 +0 −6 −12 −18 −24 FREQUENCY · Hz LEVEL · dB −3 dB Fb 35.5
DD Audio SL610 · Fb 35.5 Hz, F3 30.3 Hz
Anechoic, before any cabin gain, with the 28 Hz subsonic filter already applied. The vent takes over below 36 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 DD Audio SL610 — we do not build a sealed enclosure for it and DD 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 DD's published 19.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.

PXmax = 3097 W with a 28 Hz subsonic  ·  597 W with none  →  the filter is worth 5.2×
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 3097 W reaches Xmax here
3097 W · subsonic at 28 Hz, 24 dB/oct597 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 28 Hz subsonic that takes 3097 W, reached first at 27 Hz. Take the filter away and the same cabinet reaches 19.0 mm on 597 W — the filter is worth 5.2× 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 597 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 — DD rate this one at 600 W RMS, and that is the number that binds first here: heat stops you before travel does, so treat 600 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

Of the two DD tens in this line, this is the one with the bigger motor on paper. 29.00 Hz free-air, a 0.3720 Qts, and 26.77 litres of Vas describe a driver that is already most of the way to a vented alignment before the cabinet does anything to it. That is a very different animal from the 310e's smaller, stiffer motor.

Because the suspension is already doing so much of the work, this cabinet is tuned to 35.5 Hz, above the SL610's own 29.00 Hz resonance, in 1.352 cubic feet net. It still reaches an anechoic F3 of 30.3 Hz, and it gets there without needing to push the tuning under Fs the way a stiffer driver would require. The 23.4 square inch port only has to move air the motor is already willing to give up.

600 watts and 19.0 mm of Xmax is a real amount of driver for a chassis that only asks for 3.976 inches of mounting depth, which is why it sits comfortably in the same 7.75 inch tall down fire cabinet as the deeper-mounting 310e.

DD does not publish Sd for the SL610. The 350.8 square centimetre figure is derived from their published piston diameter through Sd = pi x (d/2)^2, not a number DD prints directly. They also publish no Mms, Cms, Re, or Xmax basis for this driver, so the panel does not carry those figures, and the 19.0 mm Xmax is used as printed with no derating convention to apply. DD gives no bolt hole locations for this basket either, so the threaded inserts are not pressed into the baffle before it ships. The threaded insert kit ships in the box instead and you set it when the woofer goes in.

DD does not specify a coil or impedance configuration for the SL610 in the data published here, so confirm the wiring at the terminal against your amplifier's rated load before you hook it up. DD sells this one in D2 and D4, and publishes a single set of parameters for both, so the box does not change with the coil. Wire the D2 4 ohms in series or 1 ohm in parallel. Wire the D4 8 ohms in series or 2 ohms in parallel. There is no published DC resistance, so trust the label on the coil in front of you.

It ships dry. Do not add polyfill to a ported box. Set your subsonic filter at 30 Hz.

Before you order

Questions

Why is this enclosure tuned to 35.5 Hz?

A well damped, high compliance motor like this one is an easy vented load: the 1.352 cubic foot net cabinet and 23.4 square inch port at 35.5 Hz do not have to fight the suspension to get a controlled result, unlike a stiffer driver where the box has to work harder to pull the response down past Fs. DD publish no vented recommendation of their own for the SL610, so the 35.5 Hz tuning here is our solve against their published T/S set, not a factory number. Tuning is chosen for in-car response rather than for an anechoic curve: a vehicle adds roughly 12 dB per octave below about 45 Hz, so a box tuned very low reinforces a region the cabin is already reinforcing and leaves 40 to 60 Hz thin. In this cabinet that lands at 6.7 dB of in-car spread across 25 to 60 Hz, which is where kick and bass fundamentals live.

Does this enclosure ship with polyfill?

No, and on this build in particular do not add any. Every sealed Proline X enclosure ships with polyfill pre-installed; a ported one must not, because damping material changes the effective volume the port is tuned against. The port on this cabinet is cut to 29.21 inches of centreline path for 35.5 Hz. Stuff it and you move the tuning without shortening the port, which gives you a mistuned box rather than a bigger-sounding one. The 3.29 dB passband you are paying for depends on it staying dry.

Do I need a subsonic filter?

Yes, at 28 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 DD Audio SL610 at 44 percent of its usable travel at full rated power; without it there is no meaningful number to quote, because the excursion curve does not converge. On a sealed build a subsonic filter is an improvement. Here it is required equipment.

How much power can I run?

DD Audio rate the SL610 at 600 W RMS and that is the thermal ceiling. The figures on the Performance Graphs tab are a different quantity: they are mechanical limits, the power at which the cone reaches the end of its linear travel in this specific cabinet. Here the cone sits at 44 percent of usable travel at the driver's own rating, so heat is what stops you, not travel. Final wired impedance and amplifier output are separate questions again.

Would a sealed box be better for me?

Not one we can show you. We do not build a sealed enclosure for the DD Audio SL610 and DD Audio publish no sealed volume for it, so the Performance Graphs tab carries no ported-versus-sealed chart: the only sealed box left to plot would be this cabinet stuffed and sealed, which nobody would build, and a comparison against it would tell you nothing you could buy. What a vented box gives up is the region below tuning, where the cone unloads and the 28 Hz subsonic filter takes over; around 35.5 Hz the vent carries the load and cone travel drops to its minimum, which no sealed alignment can do.

What is the L-wrap port and why does it matter?

It is a slot port formed by one folded wall: a leg down the long side of the cabinet past the woofer ring, one faceted 90 degree bend, and a leg across the end opening through a chamfered corner. On this cabinet that is 29.21 inches of centreline path and 23.4 square inches of channel, exiting a 30.9 square inch mouth. Air leaves at 16.0 metres per second at tuning against a 17.0 threshold, and the channel runs at 48 percent of its turbulence limit. One wall and one bend rather than a serpentine's three means less wall area inside the box, fewer joints to leak, and one place for flow to separate instead of three.

How is this enclosure built?

V-groove and dado joinery in 0.75 inch Langboard Elite MDF with a double-layer 1.5 inch baffle. The driver mounts to a 11.500 inch ring bonded under the baffle in a machined recess, carrying eight #8-32 hurricane nuts so it threads into steel rather than MDF. A windowed brace sits 2.72 inches clear of the cutout edge and 1.60 inches clear of the port terminus; the window is not weight saving, a solid panel there would split the cavity and make the box a bandpass. Walls seat into dados in both the lid and the baffle. Square corners, plush black carpet, side-mounted terminal cup.

Is the SL610 included?

No. This is an enclosure only, cut and folded for the DD Audio SL610 specifically. The 9.252 inch cutout, the 3.976 inch mounting depth allowance and the 1.35 cubic foot alignment all come from DD Audio's published parameters for this exact driver, and the port is sized against its Xmax and power rating. It is not a universal box with a 10 inch hole in it. Bring your own driver.

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