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Performance Optimized · Datasheet

Performance Optimized Down Fire Sealed 10" Shallow Sub Enclosure Rockford Fosgate T1 Slim · Single 10" Sealed enclosure

Net volume
0.99 Cubic Feet
Max mounting depth
3.00 Inches (Rockford Fosgate Spec)
External dimensions
30 Inches W × 7 Inches H × 15 Inches D
Front baffle
Double-Layer 1.5" MDF (Two 3/4" Sheets Bonded)
Buy at Audio IntensityFactory-direct, ships from Tullahoma
Rockford Fosgate T1 SlimBuy at Audio Intensity
  • Alignment: 0.99 cu ft net, Qtc 1.15 / F3 37.9 Hz (1Ω), Qtc 1.26 / F3 38.3 Hz (2Ω), underdamped by design
  • Driver: Rockford Fosgate T1S1-10 (1Ω SVC) or T1S2-10 (2Ω SVC), 500W RMS, 15mm Xmax, 3.00" mounting depth, 9.13" cutout
  • Why Qtc Is High: Free-air Qts is 0.95 (1Ω) and 1.04 (2Ω), and Qtc can never fall below Qts; this cabinet lands at 1.15 and 1.26
  • Build: Proline X V-groove and dado joinery, double-layer 1.5" front baffle, perimeter cross-brace, 12g OFC side-mounted terminal cup
  • Cabinet: 30"W x 15"D x 7"H measured in down fire position, square corners

Spec of record

Technical specifications

SeriesProline X Performance Optimized Down Fire
Compatible DriverRockford Fosgate T1S1-10 (1Ω SVC) or T1S2-10 (2Ω SVC)
Enclosure TypeSealed | Down Fire Geometry | Floor-Coupled
Firing DirectionDown Firing, Driver Fires Toward Floor
External Width30 Inches
External Depth15 Inches
External Height7 Inches
Dimension ReferenceAll External Dimensions Measured In Down Fire Position
Internal Volume (Gross)1.02 Cubic Feet
Internal Volume (Net After Displacement)0.99 Cubic Feet
Target System Qtc (T1S1-10)1.15 (Underdamped | Computed from Published T/S)
Target System Qtc (T1S2-10)1.26 (Underdamped | Computed from Published T/S)
Predicted F3 (T1S1-10)37.9 Hz
Predicted F3 (T1S2-10)38.3 Hz
Driver Free-Air Qts0.95 (1Ω) / 1.04 (2Ω), Qtc cannot fall below Qts
Driver Displacement0.03 Cubic Feet (Published by Rockford Fosgate)
Mounting Depth Required3.00 Inches (Rockford Fosgate Spec)
Woofer Opening9.13 Inches (Rockford Fosgate Spec)
Voice Coil ConfigurationSingle Voice Coil, Impedance Set By Driver Model
MaterialLangboard Elite 3/4" MDF
ConstructionShopSabre CNC / Perimeter Cross-Brace
JoineryV-Groove and Dado (CNC-Cut)
Panel Thickness3/4 Inch
Front Baffle ConstructionDouble-Layer 1.5" MDF (Two 3/4" Sheets Bonded)
Corner ProfileSquare (Down Fire Series Standard)
Driver Mounting8/32 Threaded Inserts | Stainless Steel Machine Screws Included
Terminal CupProline X ABS/Carbon Fiber Composite | Side Mounted | 12g OFC Pre-Wired
DampingPolyfill Pre-Installed
Recommended Power350-500 Watts RMS (Rockford Rated: 500W RMS Continuous)
Carpet FinishPlush Black
Bundle OptionsEnclosure Only (Bring Your Own T1S1-10 or T1S2-10)
Shipping Weight41 lb
Warranty1-Year Limited (Enclosure)
Built InTullahoma, Tennessee, USA

Modelled response

Performance in this enclosure

Net airspace
0.99
cu ft
System Qtc
1.15–1.26
sealed
Half power
37.9–38.3
Hz · F3
Xmax at
568
W RMS · no filter
With 25 Hz subsonic
574
W RMS · +1%
Amplifier
500
W RMS recommended
This enclosure holds 0.99 cu ft net . In it the Rockford Fosgate T1 Slim runs a system Qtc of 1.15–1.26 with half power at 37.9–38.3 Hz, and the cone reaches its 15.0 mm travel limit at 568 W, above the driver’s 500 W thermal rating, so heat stops you before travel does. A 25 Hz subsonic filter adds little here: 574 W against 568 W, 1 percent. The box already resonates at 51–53 Hz, so its own rolloff has removed most of what the filter would have stopped.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 37.2–40.0
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 T1S1-10 (1 ohm) 40.0 T1S2-10 (2 ohm) 37.2
T1S1-10 (1 ohm) · EBP 40.0T1S2-10 (2 ohm) · EBP 37.2
EBP under 50 means a motor that wants a sealed load. The T1 Slim sits at 37.2–40.0, inside that band, which is why this is a sealed build rather than a ported one.

02What the box does to it

0.99 cu ft against a 13.1 L Vas.

α = Vas ÷ Vb = 0.47  ·  Fc = Fs√(α+1) = 51–53 Hz  ·  Qtc = 1.15–1.26
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
T1S1-10 (1 ohm) · Qtc 1.15, Fc 51 Hz, F3 37.9 HzT1S2-10 (2 ohm) · Qtc 1.26, Fc 53 Hz, F3 38.3 Hz
The box lifts resonance from 42.0–43.5 Hz free-air to 51–53 Hz and half power lands at 37.9–38.3 Hz, anechoic, before any cabin gain. This enclosure ships without a driver, so both coil variants the maker offers are plotted. They do not load the same box the same way.

03The 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 15.0 mm, and in this alignment a subsonic filter barely moves it.

PXmax = 568 W unfiltered  →  574–580 W with a 25 Hz subsonic
20 30 50 70 100 150 200 0 4 8 12 16 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 15.0 mm 568 W reaches Xmax here
T1S1-10 (1 ohm) · 568 W, no filterT1S2-10 (2 ohm) · 568 W, no filterT1S1-10 (1 ohm) · 580 W with subsonic at 25 Hz, 24 dB/octT1S2-10 (2 ohm) · 574 W with subsonic at 25 Hz, 24 dB/octXmax 15.0 mm one-way
Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 15.0 mm. Unfiltered that is 568 W, reached first at 44 Hz. It sits above the 500 W the driver can take thermally, so the voice coil gives up before the suspension does. The dashed traces are the same driver behind a subsonic filter at 25 Hz, 24 dB/oct, and they sit almost on top of the solid ones: 574 W against 568 W. At 51–53 Hz the filter sits well below resonance, where the sealed alignment has already rolled the cone off at 12 dB/oct, so there is little wasted travel left for it to recover. Set it anyway to keep road rumble out of the cone, but do not size the amplifier around it.
ParamValueUnitNote
Fs42.00 / 43.50Hzfree-air resonance
Qts0.950 / 1.040T1S1-10 (1 ohm) / T1S2-10 (2 ohm)
Vas13.10 / 13.10Lequivalent compliance
Sd356.0cm²effective piston area
Xmax15mmone-way linear travel
Pe500Wcontinuous RMS
SPL81.5dB1 W / 1 m, derived from T/S

Driver parameters as published by loudspeakerdatabase.com. Curves computed against this enclosure’s actual net airspace.

From the shop floor

Installer's take

The T1 Slim 10 is a genuine 3 inch deep driver with a 2.5 inch four-layer coil and 15mm of one-way Xmax behind an anodized aluminum cone. For a shallow it moves real air, and Rockford put their VAST surface tech and integrated trim ring on it so the mounting face looks finished without a separate grille.

Here is the thing you need to understand about this driver before you buy a box for it, and most sellers will not tell you. Free-air Qts is 0.95 on the 1 ohm model and 1.04 on the 2 ohm. Qtc can never go below Qts. Not in a bigger box, not in an infinite baffle, not ever. That means there is no sealed enclosure on earth that puts a T1 Slim at 0.707. Every box you build for it is underdamped and will have a response peak near the corner frequency.

That is not a flaw, it is the design brief. Rockford built this driver for shallow prefab boxes where the peak plus cabin gain reads as punch and makes a thin cabinet sound much bigger than it measures. Judge it on what it is meant to do rather than against a textbook alignment it was never going to hit.

Given that, the design question is just how far down you can push Qtc, and the answer is: build big. At 0.99 net this lands at Qtc 1.15 on the 1 ohm and 1.26 on the 2 ohm, with F3 at 37.9 and 38.3 Hz. Rockford's published range tops out at 1.0 cubic feet and we are sitting right at it. A 0.5 cubic foot box would put you above Qtc 1.3 with a higher F3 and a sharper peak. Bigger is strictly better with this driver.

One note on Rockford's own manual: their sealed table lists Qtc 1.10 at 0.77 net, but computing from the driver's Qts and Vas gives roughly 1.20 on the 1 ohm at that volume. Their table runs about 0.1 optimistic against the T/S data. We publish the computed number.

Wiring is simple here because both models are single voice coil. Whatever you buy is what the amp sees. Target 350 to 500 watts RMS.

Before you order

Questions

Why is the Qtc above 1.0? Is this enclosure too small?

No, the enclosure is at the top of Rockford's published range. The high Qtc comes from the driver, not the box. The T1 Slim 10 has a free-air Qts of 0.95 on the 1 ohm model and 1.04 on the 2 ohm, and system Qtc can never fall below the driver's Qts regardless of enclosure size. Even an infinite baffle would leave this driver at 0.95 or above. There is no sealed volume that reaches a textbook 0.707 alignment with a T1 Slim, so a larger box would not fix it and a smaller one makes it worse.

What does an underdamped alignment actually sound like?

A response peak near the corner frequency, followed by a steeper rolloff below it. In practice that reads as punch and impact rather than deep extension. It is a livelier, more forward presentation than a flat alignment, which is exactly what Rockford designed the T1 Slim to deliver in the shallow prefab enclosures it was built for. In a vehicle the peak lands where cabin gain is already rising, so the effect is emphasis in the upper bass rather than a problem to solve.

Should I choose the T1S1-10 or the T1S2-10?

Both are single voice coil and both fit this cabinet identically, so the decision is about your amplifier and about damping. The T1S1-10 is 1 ohm with a free-air Qts of 0.95, landing at Qtc 1.15 in this enclosure. The T1S2-10 is 2 ohm with a Qts of 1.04, landing at Qtc 1.26. The 1 ohm model is the better damped of the two in this box. Choose based on what load your amplifier is stable into first, then take the damping difference as a secondary consideration.

How do I wire this enclosure?

Straightforward, because both T1 Slim models are single voice coil. There is no series or parallel decision to make at the driver. The enclosure has one side-mounted Proline X terminal cup pre-wired in 12 gauge OFC, and the impedance your amplifier sees is whatever model you install: 1 ohm for the T1S1-10, 2 ohm for the T1S2-10. Confirm your amplifier is stable at that load before powering the system.

Where is the terminal cup located on a down fire enclosure?

Side mounted. Every Proline X Performance Optimized enclosure uses a side mounted terminal cup regardless of alignment, whether standard, wedge, or down fire. On this cabinet that keeps the connection fully accessible with the enclosure in its installed position, since the baffle faces the floor. The cup is our Proline X ABS and carbon fiber composite unit, recessed, with stainless hardware, copper ring terminals, and pre-wired 12 gauge OFC.

Why are the corners square instead of radiused?

Down Fire cabinets are built with square corners as a series standard. The 3 inch top down corner radius used on other Proline X alignments does not apply here. A down fire box is a low, wide platform that typically sits flat against a floor or under a seat, and square corners maximize usable internal volume for a given footprint while keeping the cabinet stable on its mounting surface.

How is this enclosure built?

V-groove and dado joinery, CNC-cut on ShopSabre routers from Langboard Elite MDF. Every panel joint is a machined interlocking groove that mechanically locks the panels before adhesive is applied, which is what keeps the cabinet airtight under sustained pressure cycling. The front baffle is a double layer at 1.5 inches, two bonded 3/4 inch sheets, standard across the Performance Optimized Series. Perimeter cross-bracing and pre-installed polyfill complete the build. Assembled and inspected in Tullahoma, Tennessee.

Is the Rockford Fosgate T1 Slim subwoofer included with this enclosure?

No. This listing is for the enclosure only. Bring your own Rockford Fosgate T1S1-10 or T1S2-10. The cutout and mounting depth are direct fit for either model. We also sell the current Gen-2 Rockford Fosgate T1S2-10S, which uses the same 9.13 inch cutout and fits this cabinet.

Same series, same size

Other Performance Optimized models