1.5 Cu Ft - Single 12" Sealed MDF Subwoofer Enclosure (Belva MDFS1215)-OPEN BOX

12-inch Sealed Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.5 cu ft airspace)

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This item has been discontinued

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General Features:

  • Single Sealed 12" Enclosure
  • Internal box volume: 1.5 cubic ft
  • High Quality 3/4" MDF Construction
  • Durable black carpeting
  • Pre-lined with Poly-Fil
  • Seams are fully caulked for better efficiency
  • Gold post terminals for clean and easy wiring access
  • Box Dimensions: 16"L x 17"D x 13-1/2"H
  • 30 Day return policy

Speaker Box / Enclosure Specifications

Subwoofer Size
Refers to the diameter of the subwoofer, measured in inches.
Subwoofer Cutout Shape
This is the shape of the enclosures cutout hole and defines the style of subwoofer that can be installed.
Round / Circle
Box Type
Represents the style of the enclosure. Be sure to purchase the appropriate enclosure type and internal volume that will be compatible with your subwoofer's recommendation.

Sealed - Sealed boxes are those that have no holes or vents in it. The only hole in a sealed box is where the subwoofer is installed. Smaller sealed boxes require more power than a larger sealed box. They provide a tight, accurate bass, while the larger sealed enclosures provide a "boomier" and louder bass.

Ported / Vented - Ported/Vented Enclosures provide an even boomier, louder bass, but less accurate then a small, sealed box. Ported enclosures typically require more airspace per sub and also less power output from an amplifier to perform correctly.

Bandpass - Bandpass enclosures make subwoofers perform efficiently, but loose. The bass is not as "boomy" as a ported enclosure nor as punchy as a sealed enclosure. Bandpass enclosures work well with lower to mid-level subwoofers.
Number of Subs/Speakers
This value represents the number of speakers or subwoofers that the enclosure accommodates.
Box Style/Shape
The box style or shape refers to the actual shape of the box. Square and rectangular boxes are straight-edged boxes on all sides, whereas hatchback and truck style enclosures feature an angled front or back design that allows for installation in places short on depth such as single cab pickup trucks. You can also use such enclosures in hatchback cars or other vehicles where space is a premium. Tube and cylinder shaped boxes were made popular by Bazooka and are a great option for those looking for a nice amount of bass without sacrificing lots of space. They may even fit in locations that slim truck boxes cannot fit in. If the enclosure is vehicle specific, we encourage you to read the product description to find out which vehicles the enclosure is made for.
Cutout Diameter or Length
The actual diameter of the hole in the subwoofer box. Length is the measured length per side of a square subwoofer or speaker opening.
Maximum Speaker Depth
Your subwoofer or speaker must not exceed this dimension in order to properly mount in this enclosure.
Total Box Volume
The internal volume measurement in cubic feet before subwoofer magnet displacement.
1.5 cubic feet
Box Volume (Each Chamber)
This is the total air space inside each chamber of the empty subwoofer enclosure. By matching this value with the recommended air space of the subwoofer, you will be able to know if the subwoofer will match this box.
1.5 cubic feet
The height of the item, measured from top to bottom, in inches.
The width of the item from left to right (side-to-side) measured in inches.
The front-to-rear depth of the item, in inches. If the item is angled or slanted, this value is the bottom measurement.
Wood Thickness
The thickness of the wood the enclosure is made of, measured in inches.
Number of Terminals
The number of terminals the enclosure has. Each terminal represents 1 positive and 1 negative.
Terminal Type
Spring clip terminals work best with bare wire connections with small-gauge speaker wire, or pin-type connectors.

Binding post terminals are a sturdier, more versatile type of speaker terminal. Because binding post terminals are are threaded, you can tighten them down against the wire or connector for a tight, clean connection. The most popular style of binding post terminals is known as a "5-way binding post". This type can accept bare wire, or any of the common speaker wire connectors. Binding posts with the option to be used with banana clips are even more versatile

Spring posts are a hybrid of the two. Instead of using a thread and "screwing" them tight, they use a spring to allow the wire to fit and tighten against the terminal.

Binding posts (banana clip ready)
Box Exterior Color
The color of the enclosure's exterior/outer finish.
Box Finish
The material used on the outside of the box. Most boxes are carpeted to prevent exterior scratches; however vinyl is popular as it can often be color-matched to a near exact look of your leather factory interior.
Tuning Frequency
Compatible Vehicle Make and Model
The model of vehicle that this vehicle specific product is designed for. Please keep in mind that engine variations can affect the compatibility of the products.

Port Details

Tuning Frequency


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Warranty and Return Policy

Parts Warranty Duration
Not warranted
Labor Warranty Duration
Not warranted
Warranty Provider

Summary of Customer Ratings & Reviews

Rating Distribution

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Average Attribution Rating

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Browse 6 questions and 35 answers
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Why did you choose this?
Sonic Electronix Store
Great dimension for Beast Sub!! And 3/4 MDFa 1" Baffle in front would of been spot on but Awesome box value
christopher l a on Nov 24, 2017
The cubic feet.
Jasen J on Oct 9, 2017
Empty boxes need a sub.
Ivan B on Nov 13, 2017
Need a box
Dustin W on Oct 8, 2017
I have a Rockford Fosgate P1S4-12..this sealed box that says 1.5 cuft. it will do the job great for my 12 subwoofer?
Edrick F on Sep 10, 2014
Best Answer: Hello Edrick,

It absolutely will. The 1.5ft^3 falls right between the 0.70ft^3 - 1.80ft^3 volume recommendation, from the Manufacture; especially after displacement is figured in. Whether it will do the job for YOU, on the other hand, is going to be subjective and particular to Your taste. So, we suggest doing a bit of homework regarding the difference between Sealed and Ported enclosures.

Reply · Report · Customer SStaff on Sep 10, 2014
· Add Answer · I Have This Question Too (0)
This particular box shows to have an 11" cutout, but the speaker I'm looking at in the package deal shows to need an 11.25 cutout. When you package these shouldn't the cutout be specific for that particular speaker, or is it something that I'll have to fix?
Mark C on Aug 14, 2015
Best Answer: Hello,

Logistically speaking, we cannot shave away the 0.25" before the bundle ships. Most bundles are intended for beginners who often go to an installer to get the work done, and that installer will often make the adjustments for them. So, although we are aware that the opening is slightly smaller than needed, and will need to be manually widen, the ease of selection for customers outweighs the 'negative' of that small adjustment. More over, The cutout of a driver is often beyond the ridge of the motor/chassis, so it is likely no adjustments will need to be made at all.
Reply · Report · Rick MStaff on Aug 14, 2015
· Add Answer · I Have This Question Too (0)
Will a P2D4-12 DVC Subwoofer fit in this box? I was thinking of buying this sub woofer, and i have been reading the box is one of the most important parts of a sub woofer.
Mark A on Aug 8, 2016
Belva MDFS1215
Belva MDFS1215
Rockford Fosgate P2D4-12
Rockford Fosgate P2D4-12
Best Answer: It should fit but check the cutout diameter (hole width) and check sub's width too! I had this box once and they just asked me to answer this, but I tell you man, you should go for a quality box that has internal braces! Check out the Sound Ordnance enclosures from Crutchfield ! They have one for a 12" that is 1.83 cubic ft - a damn good box.. If you want tighter bass for rock music, get a smaller box like 1.5 cubic fr . The Belva boxes just seem hollow and cheap to be honest. Get a better one, but avoid eBay. Flimsy ones there too mostly.
Reply · Report · Beau B on Aug 8, 2016
· Add Answer · I Have This Question Too (0)
Will this box work well with: Audiopipe TXX-BD3-12 sub?
Jeffery D on Apr 13, 2017
Best Answer: Yes it will work. I have the same sub. It's not quite enough cubic space for the sub in a sealed closure. I stuffed the Box to trick it. It helped but it's still not enough air space. I would suggest finding at least a 2 Cube or a little higher for a sealed closure and that sub.
Reply · Report · Ernest C on Apr 13, 2017
· Add Answer · I Have This Question Too (0)
I thinking of pairing one of these subs with a JBO GTO-1001EZ in a 1.5 cu ft sealed enclosure, and wiring it at 4 ohm. Them amp is rated at 650W @ 4 ohm RMS. Would this be a good match?
Mark C on Sep 4, 2015
Belva MDFS1215
Belva MDFS1215
Rockford Fosgate P3D4-12
Rockford Fosgate P3D4-12
Best Answer: Hey Mark,

The Rockford Fosgate P3D4-12 is a dual 4 ohm voice coil so what that means is you can only wire it to 2ohm or 8 ohm load. If you wanted to wire it to 4 ohm load then you need to get the version with the dual 2 ohm voice coil. That way you can wire it to 1 ohm or 4 ohm load. I hope this makes sense and I did not confuse you. Please understand with any dual ohm voice coil sub regardless of brand the ohm rating on it can be doubled or cut in half depending on if you wire it in parallel or series.
Reply (1) · Report · Cliff L on Sep 5, 2015
· Add Answer · I Have This Question Too (0)

Product Summary


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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: 1.5 Cu Ft - Single 12" Sealed MDF Subwoofer Enclosure (Belva MDFS1215)-OPEN BOX

Item Added to Cart

1.5 Cu Ft - Single 12" Sealed MDF Subwoofer Enclosure (Belva MDFS1215)-OPEN BOX

12-inch Sealed Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.5 cu ft airspace)


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