Menu
Forum
General Car Audio
Subwoofers
Speakers
Amplifiers
Head Units
Car Audio Build Logs
Wiring, Electrical and Installation
Enclosure Design & Construction
Car Audio Classifieds
Home Audio
Off-topic Discussion
The Lounge
What's new
Search forums
Gallery
New media
New comments
Search media
Members
Registered members
Current visitors
Classifieds Member Feedback
SHOP
Shop Head Units
Shop Amplifiers
Shop Speakers
Shop Subwoofers
Shop eBay Car Audio
Log in / Register
Forum
Search
Search titles and first posts only
Search titles only
Search titles and first posts only
Search titles only
Log in / Join
What’s new
Search
Search titles and first posts only
Search titles only
Search titles and first posts only
Search titles only
General Car Audio
Subwoofers
Speakers
Amplifiers
Head Units
Car Audio Build Logs
Wiring, Electrical and Installation
Enclosure Design & Construction
Car Audio Classifieds
Home Audio
Off-topic Discussion
The Lounge
What's new
Search forums
Menu
Reply to thread
Forum
Car Audio Help
Enclosure Design & Construction
aeroport calculations
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Message
<blockquote data-quote="HowLowd" data-source="post: 5445852" data-attributes="member: 550161"><p>Personally just figure up in this manner then convert to round if need be.</p><p></p><p><strong>Lifted from audioques site</strong></p><p></p><p>How To Calculate Your Port Size.</p><p></p><p>The box port can be calculated with a simple formula. Box volume in cubic feet X 16 (the amount of port area in square inches per cubic feet of box volume). For example, 3.4 cuft X 16 sqin= 54.5 square inches of port area. Try to stay within 10% of this number.</p><p></p><p>The port length should be 16 inches deep. This tunes the boxes to about 40 Hz.</p><p></p><p>How To Make A Slot Port</p><p></p><p>The easiest and most effective way to build a port is to use a slot shaped port that uses 3 sides of your enclosure as port walls. If the port is located at one end of the box, only one additional piece of wood is required to complete the port. The additional piece of wood should be spaced off the end of the box.</p><p></p><p>The port area is in square inches, meaning it takes height times width to calculate total area. A port 4 inches high by 4 inches wide would calculate as 4 X 4= 16 square inches.</p><p></p><p>In our example box, we have an inside height of 14.5 inches. To calculate the slot width that would make a total area of 54.5 square inches, and we use 14.5 inches as the height: divide 54.5 by 14.5= 3.76. Round that figure to nearest ¼ inch, and you get an offset measurement of 3 ¾ inch wide. The slot port would be 3 ¾ inches wide by 14 ½ inches tall.</p><p></p><p>You don’t have to get too critical about the box and port volume, a good rule of thumb is that if you stay within 5-10% of calculated volumes, there will be very little if any audible effects.</p><p></p><p>Port Length Obstructions</p><p></p><p>Some port lengths do not allow for 16-inch port depths without some sort of modification. The rule of thumb is not to let the end of the port get any closer to the back wall than the width of the port. So back to our example, we have an internal box depth of 12.5 inches. We need a 16-inch deep port. We will have to bend the port along the back wall to get the full port length. To calculate where to make the bend, subtract the port width from the inside box depth. 12.5 – 3.75=8.75. We must bend the port at 8.75 inches, then continue the port parallel to the back wall for an additional 7.25 (8.75+7.25=16).</p><p></p><p>You now have an L shaped port totaling 16 inches in depth.</p></blockquote><p></p>
[QUOTE="HowLowd, post: 5445852, member: 550161"] Personally just figure up in this manner then convert to round if need be. [B]Lifted from audioques site[/B] How To Calculate Your Port Size. The box port can be calculated with a simple formula. Box volume in cubic feet X 16 (the amount of port area in square inches per cubic feet of box volume). For example, 3.4 cuft X 16 sqin= 54.5 square inches of port area. Try to stay within 10% of this number. The port length should be 16 inches deep. This tunes the boxes to about 40 Hz. How To Make A Slot Port The easiest and most effective way to build a port is to use a slot shaped port that uses 3 sides of your enclosure as port walls. If the port is located at one end of the box, only one additional piece of wood is required to complete the port. The additional piece of wood should be spaced off the end of the box. The port area is in square inches, meaning it takes height times width to calculate total area. A port 4 inches high by 4 inches wide would calculate as 4 X 4= 16 square inches. In our example box, we have an inside height of 14.5 inches. To calculate the slot width that would make a total area of 54.5 square inches, and we use 14.5 inches as the height: divide 54.5 by 14.5= 3.76. Round that figure to nearest ¼ inch, and you get an offset measurement of 3 ¾ inch wide. The slot port would be 3 ¾ inches wide by 14 ½ inches tall. You don’t have to get too critical about the box and port volume, a good rule of thumb is that if you stay within 5-10% of calculated volumes, there will be very little if any audible effects. Port Length Obstructions Some port lengths do not allow for 16-inch port depths without some sort of modification. The rule of thumb is not to let the end of the port get any closer to the back wall than the width of the port. So back to our example, we have an internal box depth of 12.5 inches. We need a 16-inch deep port. We will have to bend the port along the back wall to get the full port length. To calculate where to make the bend, subtract the port width from the inside box depth. 12.5 – 3.75=8.75. We must bend the port at 8.75 inches, then continue the port parallel to the back wall for an additional 7.25 (8.75+7.25=16). You now have an L shaped port totaling 16 inches in depth. [/QUOTE]
Insert quotes…
Verification
Post reply
Forum
Car Audio Help
Enclosure Design & Construction
aeroport calculations
Top
Menu
What's new
Forum list
