2018 Honda Civic Dual 12 Sealed custom enclosure render, assembled view and inside plan view

Custom Builds · Datasheet

2018 Honda Civic Dual 12 Sealed Dual 12" Sealed enclosure

Net volume: 0.61 cu ft per chamber, 1.23 total, after the posts and 0.042 cu ft driver displacement
Cutout: 11.125 in x2 at 8.688 / 25.312 in, 14 in back
External dimensions: 34.00" W x 28.00" D x 5.00" H

Request this buildBuilt to order in Tullahoma

SKU CB 12D-S CIVIC18 Dealers: paste this SKU into the order form.

Wavtech thinPRO12Request this build

Best For: 2018 Honda Civic, two Wavtech thinPRO 12s
Net Volume: 0.61 cu ft per chamber (1.23 total)
Driver Match: Pair of Wavtech thinPRO 12
Construction: Custom Build | Woofers Up | Two Sealed Chambers | Double 1.5" Top, Gloss Black Acrylic Overlay | 8 Posts | Right-Side Terminal Cup | No Carpet

Spec of record

Technical specifications

Specification	Value
Build Type	Custom Build Series: 2018 Honda Civic
Compatible Driver	Wavtech thinPRO 12, quantity 2
External Dimensions	34.00" W x 28.00" D x 5.00" H
Mounting	Woofers up, surface mount on a double 1.5 in top, no recess
Internal Volume, Net	0.61 cu ft per chamber, 1.23 total, after the posts and 0.042 cu ft driver displacement
Alignment per chamber	Qtc 0.851, fc 48.1 Hz, F3 41.3 Hz anechoic
Wavtech Recommended	0.4 to 1.0 cu ft sealed, 0.6 optimum
Cutouts	11.125 in x2 at 8.688 / 25.312 in, 14 in back
Motor Clearance	1.25 in below the 3.0 in mounting depth
Bracing	Four 3 x 0.75 in MDF posts per chamber, 8 total
Sides	Flush, no inset side panels
Terminal Cup	One, right side (28 in side), 7 in from the front edge
Driver Mounting	Threaded insert kit included; Wavtech publishes no bolt circle
Material	Langboard Elite MDF, rabbet and dado joinery
Top Finish	Gloss black acrylic overlay
Carpet	None: bare MDF for custom trim panels
Shipping Weight	64 lb
Warranty	1 Year Limited
Built In	Tullahoma, Tennessee

Modelled response

Performance in this enclosure

Net airspace

0.61

cu ft per chamber

System Qtc

0.85

sealed

Half power

41.3

Hz · F3

Xmax at

1563

W RMS · no filter

With 25 Hz subsonic

1760

W RMS · +13%

Amplifier

750

W RMS recommended

This enclosure holds 0.61 cu ft net per chamber. In it the Wavtech thinPRO 12 runs a system Qtc of 0.85 with half power at 41.3 Hz, and the cone reaches its 20.0 mm travel limit at 1563 W, above the driver’s 750 W thermal rating, so heat stops you before travel does. Run a subsonic filter at 25 Hz and that becomes 1760 W — +196 W, or 13 percent more power for the same 20.0 mm of travel.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 51.0

4 ohm · EBP 51.0

At 51.0 the thinPRO12 sits in the transition band, not the sealed band. That is not a mismatch: a transition motor works in either alignment, and sealed buys a smaller box and a gentler roll-off at the cost of some low-end output. Stage 02 shows what this airspace actually does with it.

02What the box does to it

0.61 cu ft against a 42.0 L Vas.

α = Vas ÷ Vb = 2.42 · Fc = Fs√(α+1) = 48 Hz · Qtc = 0.85

4 ohm · Qtc 0.85, Fc 48 Hz, F3 41.3 Hz

The box lifts resonance from 26.0 Hz free-air to 48 Hz and half power lands at 41.3 Hz, anechoic, before any cabin gain. Wavtech's own sealed recommendation for the thinPRO 12 is 0.4 to 1.0 cubic feet with 0.6 the optimum; each chamber of this custom box is built to it, 0.61 cubic feet net.

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 20.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

P_Xmax = 1563 W unfiltered → 1760 W with a 25 Hz subsonic

4 ohm · 1563 W, no filter4 ohm · 1760 W with subsonic at 25 Hz, 24 dB/octXmax 20.0 mm one-way

Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 20.0 mm. Unfiltered that is 1563 W, reached first at 27 Hz. It sits above the 750 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: stopping the cone wasting travel below the passband lets it take 1760 W before hitting the same 20.0 mm. That is 13 percent more amplifier for the price of one filter setting.

Param	Value	Unit	Note
Fs	26.00	Hz	free-air resonance
Qts	0.460		4 ohm
Vas	42.00	L	equivalent compliance
Sd	510.7	cm²	effective piston area
Xmax	20	mm	one-way linear travel
Pe	750	W	continuous RMS
SPL	83.5	dB	1 W / 1 m, derived from T/S

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

From the shop floor

Installer's take

Built to the car and the woofers: 34 by 28 on the floor, and the height is whatever 0.6 cubic feet per chamber needs, 5.00 inches.

That is Wavtech's own optimum for the thinPRO 12 sealed, Qtc 0.85, F3 41.3 Hz. Two chambers, so the pair never fight over air.

Woofers up through a double top with no recess, flush edges, posts instead of panel braces because the cavity is only 2.75 tall.

One terminal cup on the right side, eight posts inside, no carpet: the top gets the gloss black acrylic, the rest stays bare for the custom trim panels. Inserts ship in the kit.

Before you order

Questions

Will this fit a 2018 Honda Civic?

It was built for one: 34 inches wide, 28 deep and 5.00 tall. Measure your own trunk floor before ordering; trims and aftermarket panels vary.

Why 0.6 cubic feet per chamber?

It is Wavtech's own sealed optimum for the thinPRO 12. On Wavtech's figures it reads Qtc 0.851 with half power at 41.3 Hz.

What power should I run?

The thinPRO12-4 is rated 750 watts RMS; aim for 525 to 750 watts per driver.

Why do the woofers fire upward?

This custom build mounts the pair on the top face so the box can stay 5.00 inches tall and use the whole 34 by 28 floor.

Why two separate chambers?

Two woofers sharing one sealed volume load each other. A full divider gives each its own 0.61 cubic feet.

What is the expected low-frequency extension?

Anechoic F3 is 41.3 Hz per chamber; cabin gain in the car adds real output below that.

Is there a terminal cup?

Yes, one, on the right side (a 28 inch side) 7 inches back from the front edge. Both woofers wire to it; chamber A's leads pass through a sealed hole in the divider.

Are the woofers included?

No. Enclosure only; bring your own pair of Wavtech thinPRO 12s. You receive the cabinet with its gloss black acrylic top overlay, bare MDF elsewhere for your trim panels, and a threaded insert kit with screws.

Same series, same size