achieving SPL Levels

[snoopdan 5,000+ posts]

You also base your SPL box on what kind of vehicle you are working with. One type of SPL box for a CRX with a single sub application, will not function with the same output in a SUV. So you have to build with your vehicle in mind for this (which is another reason why people cant just get on a forum here and start claiming they sell SPL boxes for every type of vehicle (cough tcab, powered4sound, cough) and expect to actually do well on the mic.

Now there are some general SPL box strategies that you can follow, really someone should make a cliff notes for SPL box building for questions just like yours. For example, if you had a SUV with one 15" sub you'd want to make a box that has the sub and port firing backwards towards the back door. If you have that exact same SUV and have two 15's, you'll want to fire both up and port it towards the rear of the vehcile. THIS is the type of thing that needs to be explained to people with aspirations of high SPL numbers.

Dont even get me started on other vehicle types like sedans, coupes, wagons, hatchbacks, and trucks....but they all have quarks and rules to go by too.

 

[Louisiana_CRX 5,000+ posts]

Make a big box tuned to your cars resonance frequency?
Louisiana CRX. Is that what you do? Tune to resonance of car?

Actually box is tuned below car resonance freq....peaks from box match cars resonant freq....

 

[hzsogood 5,000+ posts]

doesnt bigger port automatically make the tuning higher therefore it should be louder for spl
could a bigger port be made and still keep a low tuning

the bigger the port the longer the port.. , so bigger the box

 

[mrwigglezdj 10+ year member]

well i dont know how it workd out in my van as well as it did, the box i had orignaly was built for 2 kicker cvr 15s , 19.5 cf with a wide port and tall ( 14w x 30t x 10 deep)

and it did 148 at a 61hz burp

took the same box and put a new pice of wood on the face and installed 12 10s in the same box same port same everything (other than amp power) and i do 150.4 db with a 61 hz burp and 148.7 db on music for bass boxing ..and with 12 subs and 19.5 cf of air space i have about 1.55cf per sub which is what the manufactor recomends but the big port is the key i guess along with the fact its a complety seald wall

 

[tommyk90 5,000+ posts]

the bigger the port the longer the port.. , so bigger the box

Unless you use external ports. //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

6" flared ports? Psssssssssssssssssssh

Time to play with the big boys. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[hzsogood 5,000+ posts]

Actually box is tuned below car resonance freq....peaks from box match cars resonant freq....

Whats the easiest way to figure out your box and car fs

 

[hzsogood 5,000+ posts]

Unless you use external ports. //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

Alot of ppl like aero's .. Ive never used them, But i hear good sh1t happenes with alot of ppl who swapped from stardard ported enclosures

 

[hzsogood 5,000+ posts]

Unless you use external ports. //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif



6" flared ports? Psssssssssssssssssssh

Time to play with the big boys. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Are you ever at any of the wi shows.. ?? Im assuming the southern ones ( ransom, sound mechanix ) But any ones up north ., Like eau claire or rhinelander?

 

[tommyk90 5,000+ posts]

Are you ever at any of the wi shows.. ?? Im assuming the southern ones ( ransom, sound mechanix ) But any ones up north ., Like eau claire or rhinelander?

Nope, never get up that high.

I've only done MECA shows in WI, no db drag events yet.

 

[mezman001 10+ year member]

the bigger the port the longer the port.. , so bigger the box

o.k. so knowing my boxes can or should i add ports and how long? do i make em as long as possible and back off the wall an inch or should i give more room?

 

[hzsogood 5,000+ posts]

o.k. so knowing my boxes can or should i add ports and how long? do i make em as long as possible and back off the wall an inch or should i give more room?

Depends on what subs, box size, what you want your tuning to be etc .. And like the guys above were saying matching your car and box frequency.. Which other than doing sweeps im not sure myself how to do

 

[hzsogood 5,000+ posts]

yup.. missed that one ..

I am running 2 8" mtx XS terminators with a 250 watt alpine

" " " " 10" ROKS punck XLC with a n 800 watt mono pioneer

8'2 are in a .50^3

10's are injust over a foot ^3

this is for each woofer and the box is devided but they are both seale enclosures of 3/4" mdf

__________________

First off.. Run one type and size sub

 

[mezman001 10+ year member]

Depends on what subs, box size, what you want your tuning to be etc .. And like the guys above were saying matching your car and box frequency.. Which other than doing sweeps im not sure myself how to do

info on page 1 of post

 

[mezman001 10+ year member]

yup.. missed that one ..

I am running 2 8" mtx XS terminators with a 250 watt alpine

" " " " 10" ROKS punck XLC with a n 800 watt mono pioneer

8'2 are in a .50^3

10's are injust over a foot ^3

this is for each woofer and the box is devided but they are both seale enclosures of 3/4" mdf

__________________

First off.. Run one type and size sub

please explain why?//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

 

[hzsogood 5,000+ posts]

please explain why?//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

If thats a serious question, //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif .. If not... search .. ghetto..