hitmebackl8rz Posted December 12, 2022 Report Share Posted December 12, 2022 I am looking for someone to help me with some specs for an enclosure for (8) Skar audio EVL 6.5s.... I am good at building and understand the basics, but need someone to help me with 2 things. 1) The total cubic feet for the enclosure including the port volume. 2) The total port volume. I want to use a 3-4" slot port, and would like it to be tuned to around 36Hz.... If anyone could help me out with this, I would appreciate it greatly. Here's the parameters from loudspeakerdatabase.com/Skar/EVL-65 Thanks Link to comment Share on other sites More sharing options...
Joe X Posted December 12, 2022 Report Share Posted December 12, 2022 You have the manufacturer to support you: 0.6 cubic feet per driver x 8 drivers = 4.8 cubic feet. 8.5 square inches of port area x 8 drivers = 68 square inches of port area. Notice that port volume is not part of the ported system specification port AREA is what is important. Due to the low Xmax of this drivers I wouldn't recommend this array since you volume displacement is going to be low even if you have a lot of cone area from a lot of drivers, in other words it's not going to be that loud, 3 10" subwoofers with a 19mm Xmax will displace much more air, you are going to lack deep bass compared with alternatives. Link to comment Share on other sites More sharing options...
hitmebackl8rz Posted December 12, 2022 Author Report Share Posted December 12, 2022 How is port volume not important? You have to know the length of the port..... so you're saying just make a hole in the box 10" x 6.8"???? And as far as going with other subs, that wasn't my question... I already have 8 of these.... Link to comment Share on other sites More sharing options...
Joe X Posted December 12, 2022 Report Share Posted December 12, 2022 Port volume by itself can't be used to design a box, ported boxes are defined by net internal volume, port area and tuning, all other volumes are determined later during the design process. What is necessary to know beforehand is, the maximum dimensions of the box you can fit, the type of vehicle and the model of the amplifier you will be using. Link to comment Share on other sites More sharing options...
hitmebackl8rz Posted December 12, 2022 Author Report Share Posted December 12, 2022 Ok.... let's say i have a box with internal dimensions of 30"x24" and 12" high.... That's 5 cubic ft.... And I want a 2.5" port across the 30" side...... How long would the port need to be in order for it to be tuned to 36Hz? is the answer 23.91" ??? And if it was 3" x 30" would it need to be 29.44" long to be tuned to 36 Hz? I got these numbers by plugging the Thiele and Small parameters into WINISD and setting it for 8 of them with 5 cubic ft tuned to 36Hz... I'm just not sure if I did everything correctly... Thanks Link to comment Share on other sites More sharing options...
Joe X Posted December 12, 2022 Report Share Posted December 12, 2022 No because once you put the drivers inside the box and the port inside the box you no longer have 5 cubic feet of airspace. If you want to learn to do this manually I will give you some online resources so that you can educate yourself: https://jlaudio.zendesk.com/hc/en-us/articles/224938887-Calculating-Enclosure-Volume- https://jlaudio.zendesk.com/hc/en-us/articles/204374220-Enclosure-Bracing https://jlaudio.zendesk.com/hc/en-us/articles/221068047-Enclosure-Ports Once you think you understand these perfectly, go to one of their sub manuals to solve one of their suggested designs, when you get their exact same numbers, you can try proceed with your own case: https://jlaudio.widen.net/view/pdf/xeu8lmt0i7/12W7AE_MAN.pdf Post your candidate design here and we will help you fix any issues before you actually build the box. Link to comment Share on other sites More sharing options...
hitmebackl8rz Posted December 12, 2022 Author Report Share Posted December 12, 2022 Lol... I know how to calculate the volume of a shape... Even odd shapes with angles.... I will obviously adjust the box dimensions to account for the displacement of the woofers and the port, and there will be 5 cubic ft minus the port and speakers.... You really aren't much help, huh?? You just like to look like you are.... Alrighty then.... Ummm... thanks? Even though you didn't answer my question at all... I asked how long the port would need to be for it to be tuned to 36Hz... You could have easily subtracted the port volume and the speaker displacement and told me how long to make the port to make it tuned to 36Hz.... But no.... you had to try to educate me on how to calculate volume. I took calculus in high school.. I've got volume covered... I should have known earlier you'd be no help because you said one of the things you'd need to know first is the model of amplifier I'd be using....lol...ooookay then... Cause that makes the box tuning different... Link to comment Share on other sites More sharing options...
hitmebackl8rz Posted December 12, 2022 Author Report Share Posted December 12, 2022 Let me make this really easy.... If there were 8 skar evl-65 in a box with an interior dimensions of 30"x24"x12" made of 3/4" wood, and it had a slot port 3" x 30" inside it, how long would the port need to be to have it tuned to 36Hz? Can't get much more simple than that... I didn't claim it was 5 cubic feet... Just simple box dimensions, the area of the port, and the tuning I would like.... Now how long should the port be? This should be a simple question for a man of your immense knowledge... Link to comment Share on other sites More sharing options...
Joe X Posted December 12, 2022 Report Share Posted December 12, 2022 The documents are about enclosure design, not calculate volume, that's just a smaller aspect of it, by the time you end reading you will be able to answer the question above. Also you will learn why a 3x30 port (aspect ratio of 10) breaks design rules for rectangular ports: https://jlaudio.zendesk.com/hc/en-us/articles/221068047-Enclosure-Ports Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.