How do you know when your box is too big?

[Ric Thornton]

Fecupe is right on.

And to just clear this up, the 12's only do a 53

And maybe "slightly" over 500 boxes.

Carry on

LMAO

[BJD3]

Thanks for the shout out man , i don´t consider myself a good builder just yet but yes, i´ve built a couple of good boxes already, luck maybe? i dunno lol, but i honestly prefer big ass boxes where i don´t need lots of power since that´s way more expensive, at one time i needed a Soundigital 8K for been able to bass race a 149.9 with 4 12´s , now i can do it with a 3K amplifier on same subs, how?? well, on my SPL gains testing i was able to get lots of knowledge about my subs and car, i´m still learning this : "Box it´s built not only for the subs but also for the car" , every application is different, but once you know your car, everything you built for it is gonna be stupid loud.

Now to the subject, you have to play with not only power, but also with subs specs, there are lots of people taking into account the BL, QES , SD and lots of things when they are building a box, i´ve learned that there are only 2 things i care about on a sub when i´m deciding what size of box i´m gonna use, once again, i´m still learning, but i care about QTS and VAS, the higher they are the bigger i can go on the box without caring that much about power. Said that, i´m gonna give you an example:

I got a very nice help from strongmandesigns about efficient boxes with low power, i built a box with 2 DD´s 2512(750 watts each sub) 5.8 cubic feet and 3 6" PVC ports with a 39 hz tuning, yes thats right´, 2.9 c/f per 12" , anyways, i managed to keep the f3 very low with a high tuning, with that 39 hz tuning i can play very strong from 30 hz to 50 hz with a 42 hz peak, what power am i using???? only 1200 watts hitting almost 147 dbs and box is no way near to be finished, funniest thing is that, i tried a 3K amplifier on that box and raise my score almost 2 dbs without subs bottoming out!!!! How come??? well, because my subs LOVE big boxes, and i´ve learned a lot about the acoustic of my car.

I´m sorry for writing such a long post, but i prefered to show you why i use big boxes depending on the parameters of the subs, once again, yes the bigger the box the less power the sub can take, but this is defined by the parameters of the sub, not only because of the cone area, lots of people say a 10" should work with a 1.25 - 1.5 c/f box, i used my DD 1510´s on lots of boxes and best i found with a regular amount of power was 2 c/f

I'm really liking how this thread is going.

Qts. What exactly is it? I think its the Q of the subwoofer as a whole, but what is the "Q"? And what would a high QTS be?

[Ray]

you know as well as I do Ric, its hard to keep count. Nor do i want to think about all that time behind the saw or all the mdf dust inhaled.

Good times though

[recockulus1]

Thanks for the shout out man , i don´t consider myself a good builder just yet but yes, i´ve built a couple of good boxes already, luck maybe? i dunno lol, but i honestly prefer big ass boxes where i don´t need lots of power since that´s way more expensive, at one time i needed a Soundigital 8K for been able to bass race a 149.9 with 4 12´s , now i can do it with a 3K amplifier on same subs, how?? well, on my SPL gains testing i was able to get lots of knowledge about my subs and car, i´m still learning this : "Box it´s built not only for the subs but also for the car" , every application is different, but once you know your car, everything you built for it is gonna be stupid loud.

Now to the subject, you have to play with not only power, but also with subs specs, there are lots of people taking into account the BL, QES , SD and lots of things when they are building a box, i´ve learned that there are only 2 things i care about on a sub when i´m deciding what size of box i´m gonna use, once again, i´m still learning, but i care about QTS and VAS, the higher they are the bigger i can go on the box without caring that much about power. Said that, i´m gonna give you an example:

I got a very nice help from strongmandesigns about efficient boxes with low power, i built a box with 2 DD´s 2512(750 watts each sub) 5.8 cubic feet and 3 6" PVC ports with a 39 hz tuning, yes thats right´, 2.9 c/f per 12" , anyways, i managed to keep the f3 very low with a high tuning, with that 39 hz tuning i can play very strong from 30 hz to 50 hz with a 42 hz peak, what power am i using???? only 1200 watts hitting almost 147 dbs and box is no way near to be finished, funniest thing is that, i tried a 3K amplifier on that box and raise my score almost 2 dbs without subs bottoming out!!!! How come??? well, because my subs LOVE big boxes, and i´ve learned a lot about the acoustic of my car.

I´m sorry for writing such a long post, but i prefered to show you why i use big boxes depending on the parameters of the subs, once again, yes the bigger the box the less power the sub can take, but this is defined by the parameters of the sub, not only because of the cone area, lots of people say a 10" should work with a 1.25 - 1.5 c/f box, i used my DD 1510´s on lots of boxes and best i found with a regular amount of power was 2 c/f

I'm really liking how this thread is going.

Qts. What exactly is it? I think its the Q of the subwoofer as a whole, but what is the "Q"? And what would a high QTS be?

As a general guideline, Qts of 0.4 or below indicates a transducer well suited to a vented enclosure. Qts between 0.4 and 0.7 indicates suitability for a sealed enclosure. Qts of 0.7 or above indicates suitability for free-air or infinite baffle applications. However, there are exceptions!

[BJD3]

It really depend on how big the box is? The bigger box doesn't really meant it bad because when you put the sub, bracing, and double baffle it shrink the box. Having box too big or small bad. The size do matter with the port, volume, sub displacement, bracing, and etc because it will affect the tuning frquency. I usually like to stay in the manufacturer specs becuase it sound much better than i expect. Buidling your own box much better than prefab box, only if you knowlegdegs on calculating and cutting..

I think I'm a little past that point. lol The box I have right now is tuned low, but size wise it .05 cubes below spec. Graphing it out in WinISD, a spec box tuned to 35 would give me an F3 of 33 hz. That's higher than I'd like. I want to dip down to mid-high 20s. Or at the very least, give me more output.

I just want to get all I can out of the equipment I've already bought. I may not have the best of the best, but I don't have junk either. I should be performing better than I am. Hence the question.

That and I'd like to stop giving out bad information. lol

[fecupe2001]

if Ray aproved that i´m right on, then i guess i´m doing thigs correct so far hehe, thanks for the kind comment good sir, i haven´t built 500 boxes like you have, but i´m a "professional" box builder with 3 boxes designed so far, just like elite designs hahahaha

[Reilly]

As for recommended enclosures....as stated, the manufacturers are recommending based on output and musicality. But, sometimes when I read the printed specs, I think, how do they make a speaker and not real world test it. Cause the specs are really far off.

Big and efficient, sums it up. Good on putting it out there Fecupe.

Op,

Too big, the sub unloads and pops easy. Becomes very one dimensional, usually just plays lows(depending on tuning).

[fecupe2001]

Thanks man, glad i can help, i ain´t posting the box i talked about just yet since it´s not finished, but i will in a couple of weeks with pictures of all the build, specs, score and all the good stuff so i can help people out that are using 2 good 12´s on small power

[fecupe2001]

Op,

Too big, the sub unloads and pops easy. Becomes very one dimensional, usually just plays lows(depending on tuning).

You are right about peaking low even with a high tuning, but about the unloading issue, you are almost correct, you can always fight against this by using a loading wall, i saw a vid of Ric´s truck demoing terry brocks, he has a big ass box for a 10" just like he said, he´s using sub and port side, i´m pretty sure he´s doing it because the side of the car helps to control the cone acting like a loading wall since he´s using a big ass efficient box, but i might be wrong, would like to get his input on this

[Supercharged DCs]

Best thread ever.