My friend and I are starting to build a system for his 2004 Tahoe.  We are running 4 sp4 18s. We was wondering what kind of air space and tuning we should run.  The amp we are using is an American Bass VFL1100.1.  Your help is appreciated.

What kind of music do you listen to, and how much space are you willing to sacrifice.

You sure you wanna start out on a system that big? Looks like you need a little more experience for this gratitude of a build. Do some research and read up on enclosures and please look at fi before..you order they state what is optimal performance.

alot will determine wht size you will want, SPL, or more for lows, or a balance of both. Personally I would do around 26cuft net. 

BTW, horrible first post.

Edited January 16, 201411 yr by swift

My sp4 15 is in a 4 cu box tuned @ 34 and it eats anything below 40hz so if you love the lows i'd imagine 4 18s would great in a nice big box tuned around there. Idk if this helps at all

My sp4 15 is in a 4 cu box tuned @ 34 and it eats anything below 40hz so if you love the lows i'd imagine 4 18s would great in a nice big box tuned around there. Idk if this helps at all

On how much power?

Only about 1100 for now, i really need to get something like a sundown saz 2500. Or anything that will give the sub between 2500-3500 watts. But i'm strapped with money right now and only have about $400 to spend on an amp

Only about 1100 for now, i really need to get something like a sundown saz 2500. Or anything that will give the sub between 2500-3500 watts. But i'm strapped with money right now and only have about $400 to spend on an amp

Thats enough power to get it sounding great!

What the 1100?

What the 1100?

Yes sir.

Oh yeah! It's a third underpowered and it's stupid loud for daily. Can't get enough of that 4" coil lol

It isn't underpowered. 

Oh yeah! It's a third underpowered and it's stupid loud for daily. Can't get enough of that 4" coil lol

I agree 100%.

What do you mean?

It isn't underpowered. 

What do you mean?

I mean, you aren't underpowering the sub, there is no such thing. 

 

Don't confuse the RMS rating of the subwoofer with power requirement, how loud it will be or anything else.  It has absolutely nothing to do with any of these things.

I mean, you aren't underpowering the sub, there is no such thing. 

 

Don't confuse the RMS rating of the subwoofer with power requirement, how loud it will be or anything else.  It has absolutely nothing to do with any of these things.

It's a thermal limit right?

I mean, you aren't underpowering the sub, there is no such thing. 

 

Don't confuse the RMS rating of the subwoofer with power requirement, how loud it will be or anything else.  It has absolutely nothing to do with any of these things.

Oh okay i see what you're saying. Agreed

Yes, thermal limit.  And until you model your alignment, you, nor anyone else on the planet, can tell you what amount of power is required to full output, period.

 

Your particular enclosure may have max output at 1500, 3000, 9000, or 10,000 watts (etc.), frequency dependent, you simple just don't know...

Nevermind...LOL he explained.

Edited January 16, 201411 yr by Leedogg

Yes, thermal limit.  And until you model your alignment, you, nor anyone else on the planet, can tell you what amount of power is required to full output, period.

 

Your particular enclosure may have max output at 1500, 3000, 9000, or 10,000 watts (etc.), frequency dependent, you simple just don't know...

So are you saying that the maximum output that my sub could produce is based upon the enclosure it's in. And that, that number is not a number that can be determined?

It is based (mostly) on the enclosure, or the thermal limits of the driver, whatever comes first.  It can be determined by modeling and/or ACCURATE and OBJECTIVE measurements with CALIBRATED ACCURATE test equipment...

Oh yeah! It's a third underpowered and it's stupid loud for daily. Can't get enough of that 4" coil lol

I agree 100%.

Thanks for the minus 1 asshat.

Oh yeah! It's a third underpowered and it's stupid loud for daily. Can't get enough of that 4" coil lol

I agree 100%.

Thanks for the minus 1 asshat.

Oh shit sorry did i do that? Of so i didn't mean to. I'm on an ipad and i might've scrolled/touched that. Sorry

It is based (mostly) on the enclosure, or the thermal limits of the driver, whatever comes first.  It can be determined by modeling and/or ACCURATE and OBJECTIVE measurements with CALIBRATED ACCURATE test equipment...

So typically car audio enclosure designers can measure these numbers? Like maybe for instance Pete from PWK designs?