Built an enclosure to manufacturer's specs, sounds worse than old box

[AudioGeek]

I have 2 Alpine SWE-10S4 10" subs, powered by a 500W RMS Alpine amp. I had them on a wood plate that formed a large box with part of my trunk. It would move around so it wasn't properly sealed, and it is way larger than the suggested volume for these subs.

So I decided to make a sealed enclosure. I used 3/4" MDF, and made a 12" x 24" x 7" box for these subs. The suggested volume for a sealed box for one sub is 0.5 – 0.85 cu ft. So for two subs, that box should be a good size.

However, this box sounds terrible compared to the old box. There is way less volume output, and way worse bass/frequency response.

Anyone know where I could have gone wrong?

Click to read more...

 

[Jeffdachef 5,000+ posts]

I have 2 Alpine SWE-10S4 10" subs, powered by a 500W RMS Alpine amp. I had them on a wood plate that formed a large box with part of my trunk. It would move around so it wasn't properly sealed, and it is way larger than the suggested volume for these subs.
So I decided to make a sealed enclosure. I used 3/4" MDF, and made a 12" x 24" x 7" box for these subs. The suggested volume for a sealed box for one sub is 0.5 – 0.85 cu ft. So for two subs, that box should be a good size.

However, this box sounds terrible compared to the old box. There is way less volume output, and way worse bass/frequency response.

Anyone know where I could have gone wrong?

way too small of a box for 2 tens. 12x24x7 BUT you have to subtract the thickness of the wood . from 1.1 cubic feet all of the sudden turns to .75 cubic feet. This is call NET airspace. You only accounted gross or total cubic feet which is just the size of the box, not how much usuable airspace the sub actually has.

You have a total of .75 cubic feet of airspace for 2 10s and the subwoofer itself takes up space to realistically you are cramming them in a 0.5 ish cubic box meant for only a single 10. Therefore suffocating the living daylight out of them. Having them in the same chamber fighting for air in a sealed design will also make them fight eachother for airspace, need to seperate them into individual chambers.

I'd recommend building a proper box using a box design thats actually done right. like these down below

*OFFICIAL* Free Ported Box Plans (56k NO!!) - SRT Forums - SRT4, SRT6, SRT8, SRT10 & Dodge Forum

Go ported, those are free designs with cutout sheets that work well easy to build. Once you go with a proper ported box you'll never ever want to go back to sealed again. I'd recommend doing the 2.5 cubic feet tuned to 32 hz box for nice and deep low end.or a 2.0 cubic feet box tuned to 34hz for overall sound quality and loudness. Will sound and perform miles better then what you had before.

 

[Ridinhi 5,000+ posts]

I have 2 Alpine SWE-10S4 10" subs, powered by a 500W RMS Alpine amp. I had them on a wood plate that formed a large box with part of my trunk. It would move around so it wasn't properly sealed, and it is way larger than the suggested volume for these subs.
So where they Infinite baffle?

 

[AudioGeek]

way too small of a box for 2 tens. 12x24x7 BUT you have to subtract the thickness of the wood . from 1.1 cubic feet all of the sudden turns to .75 cubic feet. This is call NET airspace. You only accounted gross or total cubic feet which is just the size of the box, not how much usuable airspace the sub actually has.
You have a total of .75 cubic feet of airspace for 2 10s and the subwoofer itself takes up space to realistically you are cramming them in a 0.5 ish cubic box meant for only a single 10. Therefore suffocating the living daylight out of them. Having them in the same chamber fighting for air in a sealed design will also make them fight eachother for airspace, need to seperate them into individual chambers.

Okay thanks, I wasn't sure if you were supposed to account for the subwoofer itself taking space, or the thickness of the wood. That makes sense now. The speakers are barely moving compared to before.

So where they Infinite baffle?

Well, here's an example of a box someone made for the same style car: http://www.camarozone.com/forum/members/2071-albums352-picture2411.jpg

So mine was just the top piece of that box, supported by two 2x4s.

 

[Jeffdachef 5,000+ posts]

thats an example of infinite baffle. Not many subs nowadays are made to perform well in infinite baffle anyways. Make the ported box and you'll be amazed.