Performance Optimized · Datasheet

Performance Optimized Wedge Sealed 15" Enclosure Audiomobile Encore 4415 · Single 15" Sealed enclosure

Net volume
1.50 cu ft after the brace and an estimated 0.12 cu ft driver displacement
Max mounting depth
5.9 in required; 0.75 in clearance above the motor against the raked rear panel
External dimensions
26.79 in W × 18 in at the seat face H × 13.31 in at the base D
Front baffle
1.5 in double baffle, outer layer machined as a flush recess
Buy at Audio IntensityFactory-direct, ships from Tullahoma
  • Best For: Audiomobile Encore 4415 Trunk-Fit Builds
  • Net Volume: 1.50 cu ft (1.63 cu ft Gross)
  • Alignment: Qtc 0.988, fc 51.1 Hz, F3 40.4 Hz; 1.2 dB rise near 73 Hz, the Encore's own character
  • Driver Match: Audiomobile Encore 4415 (dual 4 ohm)
  • Construction: Rear-Firing Wedge | V-Groove/Dado | Double 1.5" Baffle | Threaded Insert Kit included

Spec of record

Technical specifications

SpecificationValue
SeriesProline X Performance Optimized Wedge
Compatible DriverAudiomobile Encore 4415, quantity 1. Direct fit
ConfigurationSingle 15 inch, single chamber sealed wedge
Mounting PositionTrunk or cargo area, tall face against the rear seat back
Firing DirectionRearward into the trunk. Not a down fire design, no feet included
External Width26.79 in
External Height18 in at the seat face
External Depth13.31 in at the base, tapering to 6.76 in at the top
Internal Volume, Gross1.63 cu ft
Internal Volume, Net Acoustic1.50 cu ft after the brace and an estimated 0.12 cu ft driver displacement
Driver Mounting Depth5.9 in required; 0.75 in clearance above the motor against the raked rear panel
Audiomobile Sealed Range1.25 to 1.8 cubic feet; sheet minimum 1.2 cu ft (35 L)
AlignmentQtc 0.988, fc 51.1 Hz, F3 40.4 Hz anechoic; 1.2 dB rise near 73 Hz
Butterworth VolumeAbout 8 cu ft, not a practical box for this driver; every volume in Audiomobile's range sits near Qtc 1.0
Woofer Opening14.00 in (356 mm) direct fit
Frame Outer Diameter15.50 in (394 mm), Audiomobile spec
Bolt CircleNot published by Audiomobile; see Driver Mounting
Driver Displacement0.12 cu ft, estimated; not on Audiomobile's sheet
Fs / Qts / Qes / Qms32.3 Hz / 0.625 / 0.659 / 11.827, coils in parallel
Vas / Mms / Cms / Bl63.70 L / 335.99 g / 0.067 mm/N / 13.5 T-m
Driver Sd819.40 cm2, published by Audiomobile
Xmax19.1 mm one way at 70 percent Bl; 46 mm peak to peak mechanical
DC Resistance1.71 ohm with the 4 ohm coils in parallel
Driver SensitivityReference efficiency 0.313 percent, Audiomobile spec; about 87.0 dB at 1 W derived from it
Driver Power Handling1000 W RMS / 2000 W maximum
Wiring OptionsDual 4 ohm coils: 2 ohm in parallel, 8 ohm in series
Voice Coil3 in (76 mm) dual 4 ohm, Le 0.965 mH at 1 kHz
Parameter SourceAudiomobile Encore Series specification sheet (Klippel data); dealer tables print a second set that is not used
MaterialLangboard Elite MDF
ConstructionCNC cut, V-groove and dado joinery
Panel Thickness0.75 in
Front Baffle1.5 in double baffle, outer layer machined as a flush recess
Internal BracingWindowed brace, dadoed to the shell
Driver MountingThreaded insert kit included, NOT pre-installed: Audiomobile publish no mounting hole locations
Terminal CupsOne Proline X ABS and carbon fiber composite, side mounted, pre wired 12 gauge OFC
Acrylic InsertGloss black acrylic baffle insert standard
DampingLight polyfill wall lining, does not alter acoustic volume
CarpetPlush black
Shipping Weight48 lb
Warranty1 Year Limited
Built InTullahoma, Tennessee

Modelled response

Performance in this enclosure

Net airspace
1.50
cu ft
System Qtc
0.99
sealed
Half power
40.4
Hz · F3
Xmax at
1749
W RMS · no filter
With 25 Hz subsonic
1820
W RMS · +4%
Amplifier
1000
W RMS recommended
This enclosure holds 1.50 cu ft net . In it the Audiomobile Encore 4415 runs a system Qtc of 0.99 with half power at 40.4 Hz, and the cone reaches its 19.1 mm travel limit at 1749 W, above the driver’s 1000 W thermal rating, so heat stops you before travel does. A 25 Hz subsonic filter adds little here: 1820 W against 1749 W, 4 percent. The box already resonates at 51 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 = 49.0
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 4415, dual 4 ohm coils in parallel 49.0
4415, dual 4 ohm coils in parallel · EBP 49.0
EBP under 50 means a motor that wants a sealed load. The Encore 15 sits at 49.0, inside that band, which is why this is a sealed build rather than a ported one.

02What the box does to it

1.50 cu ft against a 63.7 L Vas.

α = Vas ÷ Vb = 1.50  ·  Fc = Fs√(α+1) = 51 Hz  ·  Qtc = 0.99
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
4415, dual 4 ohm coils in parallel · Qtc 0.99, Fc 51 Hz, F3 40.4 Hz
The box lifts resonance from 32.3 Hz free-air to 51 Hz and half power lands at 40.4 Hz, anechoic, before any cabin gain. Figures are from Audiomobile’s own Encore Series sheet, measured with the two 4 ohm coils in parallel. The 4415 is a high-Qts driver by design: with Qts 0.625 against 2.25 cubic feet of Vas it sits at Qtc 1.04 at Audiomobile’s 1.25 cubic foot minimum and 0.94 at 1.8, and a maximally flat box would take 8 cubic feet. At 1.50 cubic feet it lands at Qtc 0.99 with a 1.2 dB rise centred near 73 Hz, which is the impact Audiomobile builds this driver for; this page shows that curve, not a flat one. The dual wedge holds the same per chamber, so these numbers describe it too.

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 19.1 mm, and in this alignment a subsonic filter barely moves it.

PXmax = 1749 W unfiltered  →  1820 W with a 25 Hz subsonic
20 30 50 70 100 150 200 0 4 8 12 16 20 24 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 19.1 mm 1749 W reaches Xmax here
4415, dual 4 ohm coils in parallel · 1749 W, no filter4415, dual 4 ohm coils in parallel · 1820 W with subsonic at 25 Hz, 24 dB/octXmax 19.1 mm one-way
Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 19.1 mm. Unfiltered that is 1749 W, reached first at 36 Hz. It sits above the 1000 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: 1820 W against 1749 W. At 51 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
Fs32.30Hzfree-air resonance
Qts0.6254415, dual 4 ohm coils in parallel
Vas63.70Lequivalent compliance
Sd819.4cm²effective piston area
Xmax19.1mmone-way at 70 percent Bl, Audiomobile's own basis
Pe1000Wcontinuous RMS
SPL87.0dB1 W / 1 m, derived from T/S

Driver parameters as published by Audiomobile Encore Series specification sheet (Klippel data). Curves computed against this enclosure’s actual net airspace.

From the shop floor

Installer's take

This is a Qtc 1.0 box and that is the driver, not the cabinet: the Encore 4415 cannot reach 0.707 in any volume a car will hold, and every volume in Audiomobile's own range sits within a few hundredths of where this one lands. If a customer asks for flat, the answer is a different driver, not a bigger box.

Inserts ship in the kit, not pressed: Audiomobile publishes no hole pattern for the Encore. Mark from the driver, drill, press. If we get the hole locations later this changes to pre-installed.

Fitment: the 5.9 inch motor clears the raked rear panel with 0.75 to spare. Two 4 ohm coils per driver, 2 ohms in parallel, 8 in series.

Audiomobile's Klippel sheet and the dealer spec tables disagree on this driver. The sheet reproduces its own moving mass from its compliance and is what this cabinet is built to; say so if a customer brings the other numbers.

Polyfill is already in as a wall lining. Adding more makes the box act larger and walks the alignment off the volume it was built to.

Before you order

Questions

Does this fit the Audiomobile Encore 4415, and will any other 15 inch fit?

The Encore 4415, yes: the baffle is cut to Audiomobile's 14.00 inch cutout, the recess to its 15.50 inch frame, and the raked rear panel clears the 5.9 inch motor with 0.75 inch to spare. The Encore ships in one version, dual 4 ohm, so there is no coil variant to choose.

Any other 15, no. The airspace is engineered around the Encore 4415's 0.625 Qts and 63.70 liters of Vas, and a different woofer that happened to drop into the hole would not see the alignment printed on this page.

Why 1.50 cubic feet, and why is the Qtc so close to 1.0?

1.50 cubic feet is the middle of Audiomobile's 1.25 to 1.8 cubic feet sealed range for this driver. The Encore 4415 is a high-Qts design: Qts 0.625 against 2.25 cubic feet of Vas means it lands at Qtc 0.94 even at the top of Audiomobile's range and 1.05 at the bottom, and a maximally flat 0.707 box would take about 8 cubic feet, which no trunk wedge can hold.

In this cabinet it sits at Qtc 0.988, resonance 51.1 Hz, half power 40.4 Hz, with a 1.2 dB rise centred near 73 Hz. That is the punch Audiomobile builds the Encore for, and the performance graph on this page shows the real curve rather than a flat one.

What amplifier power should I run, and how should I wire it?

Audiomobile rates the Encore 4415 at 1000 watts RMS and 2000 watts maximum, so target 700 to 1000 watts RMS at the final impedance. Each driver carries two 4 ohm coils: parallel for 2 ohms (1.71 ohms DC, the way Audiomobile measured it), series for 8 ohms.

A 2 ohm load is within most monoblocks' rating, but confirm your amplifier's minimum stable impedance before you wire it; 8 ohms in series is the safe answer on any amplifier at the cost of output.

Why the wedge angle, and why rear-firing into the trunk?

The seat-side face carries a 20 degree rake that matches the lean of a factory rear seat back, so the cabinet sits flush against it and the cargo space in front stays usable. The baffle is the vertical trunk-lid-side face, so the driver fires rearward into the trunk cavity.

The trunk acts as an acoustic extension for the sealed box, and the cabin's transfer function adds real output below 50 Hz, so in-vehicle response runs deeper than the anechoic 40.4 Hz on this page.

Why is the front baffle double-layered?

The baffle is two bonded 3/4 inch sheets, 1.5 inches through. A subwoofer pushes as hard against its mounting surface as it does against the air, and a single 3/4 inch panel flexes under that load, which smears output and works the driver loose over time.

The outer layer is machined as a flush recess to Audiomobile's 15.50 inch frame, so the driver bolts to the inner layer and sits flush with the gloss black acrylic insert.

What is the expected low-frequency extension?

Anechoic F3 is 40.4 Hz with system resonance at 51.1 Hz. At Qtc 0.99 the response rises 1.2 dB around 73 Hz before rolling off, so half power sits below resonance; that lift is the Encore's designed-in impact.

Those figures exclude cabin gain. In a car the transfer function of the cabin adds real output below 50 Hz, so in-vehicle response runs deeper than the numbers above. Audiomobile's sheet publishes no in-box F3 for this driver.

Do I need to add polyfill or damping?

No. Polyfill is already installed as a light wall lining to control internal reflections, and the quantity is chosen so it does not change the acoustic volume.

Do not add more. Packing a sealed box with fill makes it behave as though it were larger, which walks the alignment away from the 1.50 cubic feet this cabinet was built to.

Is the driver included, and are the threaded inserts installed?

No driver. This is an enclosure only. You receive the cabinet finished in plush black carpet with the gloss black acrylic baffle insert, one side-mounted pre-wired terminal cup, the polyfill lining already in place, and the threaded insert kit with stainless machine screws.

The inserts ship loose on purpose: Audiomobile publishes no mounting hole locations for the Encore, so you set the driver in the recess, mark its holes, drill and press the inserts. The Audiomobile Encore 4415 is purchased separately, and the cabinet is cut direct fit to it, not a general purpose 15 inch box.

Same series, same size

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