This calculator is designed for front-firing subwoofer enclosures with a front firing slot port. Provide some basic information and it will give you cut list (but no detailed drawings, at least not yet). The calculator should throw an error message if you attempt to design a box that is not feasible. To build your box you will need a circular saw with an edge guide (or a table saw) to make the main cuts then you will need either a jig saw or a router with a circle jig to cut out the speaker holes. Finally you will need a jig saw and a router with a flush trim bit to cut and trim the brace and the port opening. If you don’t have a router check the “No-router cut list” option before you generate your cut list. Examples boxes pictured, how to videos are at the bottom of this page. Be sure to read the disclaimers before using the calculator.

Slot Port Cut List Generator — v4.2

Slot Port Cut List Generator

Enclosure Width (in): Enclosure Height (in): Maximum Allowed Depth (in): Port Width (in):

Net Internal Volume (ft³): Enter your target net airspace (the usable volume you’re aiming for).
This calculator subtracts port displacement, bracing, and the Subwoofer Displacement you enter below.

Subwoofer Displacement (ft³):

How do I estimate this?

Unfortunately most manufacturers do not provide accurate data on the amount of space the subwoofer takes up in the enclosure so you will probably need to take a guess. It is usually a lot less than you think it is. A 6" diameter magnet that is 2" thick, for example, takes up about 0.03 cubic feet. An 8" diameter magnet that is 4" thick will take up about 0.12 cubic feet. You will have to make an educated guess. There is no need to account for bracing, the calculator assumes corner 45's and a window brace from the front to the back of the enclosure.

Desired Tuning Frequency (Hz): Material Thickness (in): Double Baffle Subwoofer Mounting Depth (in): Subwoofer Cutout Diameter (in): Number of Subwoofers: Subwoofer Outside Diameter (in): No-router cut list (no need to flush-trim the port opening with a router)

Cut List

Label	Width (in)	Height (in)	Quantity

Bracing (as needed)

Label	Width (in)	Height (in)	Quantity

Bracing: Included in calculations.

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