NEED Help Understanding building slot port box!!

[mikey7182 10+ year member]

So I have always built sealed enclosures, partly because I don't really listen to anything with lower resonating bass (I like the double bass pedal on Mudvayne!) but also because I don't really know how. Just never learned I guess. SO I have a few questions for those of you who are knowledgable in this arena:

(I have already done numerous searches and not really found what I'm looking for- sorry)

First off, I followed a link in a thread on here I found in a search that talks about calculating port length, box volume, etc. But i was confused when the port length came out to be way longer than I would have room for in the box. What I would like to build (for 2 Alpine SWR-1022Ds) is a slot ported box (i think). I don't really want to lose my punchy double bass lines but I would like to see them extend lower and put out a bit more volume. I for some reason have never had the Type R 10s put out as much as I have heard in other peoples' vehicles. Will a slot port box help me accomplish this? From some things I've read on here, sealed boxes can actually be a bit louder and lower? I guess I've never experienced that.

Also, what determines what frequency you tune the port at? It isn't going to be for competition, and music plays all over the frequency range, so what are the advantages of tuning it to say 32Hz vs. 40Hz, etc? Also, what determines what that frequency is, and how do you figure out how the box needs to be built to 'tune' the box? Like I said, I am new to this side of things...

I had 3 SWR-1022Ds in my Altime SE-R about a year ago, and they sounded good but they just didn't have that gut wrenching "HIT" like I've heard in a lot of other vehicles. They were run off one MRD-M1005 so I may have been underpowering them (@2.67Ohms) but I will be using the same amp to run 2 of them now, so they should see an easy 500w each RMS. I'd really like to be more impressed with the sub stage than I have been in the past.

Sorry for the novel- hopefully a few people can step in and give me suggestions! I should have about 36" across, 14" deep and 13" tall to work with in terms of box dimensions (trunk of an '03 Maxima). Might have a bit more or less- haven't measured exactly. Thanks guys!

Mike

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[mikey7182 10+ year member]

nobody?

 

[Jacobman 10+ year member]

Heres some boxes you can use, maybe one will work.

http://www.caraudio.com/forum/showthread.php?t=137804

 

[mikey7182 10+ year member]

Great link... thank you //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Alpine's site calls for pretty specific parameters for the 'optimal vented enclosure' and yet the port length is longer than any of the dimensions of the box... are they saying it needs to be a slot port with a 90* angle in it and the length of the port is the entire length including the angle? If so, how do you determine how long to make each section of the port?

Thanks guys...

Mike

 

[mikey7182 10+ year member]

Great link... thank you //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Alpine's site calls for pretty specific parameters for the 'optimal vented enclosure' and yet the port length is longer than any of the dimensions of the box... are they saying it needs to be a slot port with a 90* angle in it and the length of the port is the entire length including the angle? If so, how do you determine how long to make each section of the port?

Thanks guys...

Mike

 

[mikey7182 10+ year member]

Now when you're building a ported box for multiple subs, is it better to seal off each chamber/sub individually? In other words, similar to a sealed enclosure, where each sub enclosure is separated by a piece of MDF or whatever, is it a good idea to do this when building a ported enclosure? I think I've got a decent grasp on how to build one now so I'm just trying to figure out doing 2 subs instead of 1. If I go off Alpine's specs for vented box, what I was thinking is building one large enclosure with one vent/port on each side (basically duplicating their instructions and mirroring them) and have both subs in the middle, separated by MDF so that each vented enclosure is separate from the other. Is this that important? Thanks!

Mike