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View Full Version : Odd shaped enclosures sound funny?



valin
05-28-2009, 07:23 PM
Would an odd shaped enclosure cause a driver to sound crappy? I'm trying to troubleshoot my system, and currently have issues everywhere.

The enclosure is 2.0 cubes, sealed, after displacement, and is completely sealed inside with resin and fiberglass, but it sounds like crap. I am wondering if it might have something to do with the limited mounting depth, and box shape.

Any ideas?


http://i184.photobucket.com/albums/x241/ryanvalin/Tundra/TundraStereo001-2.jpg

http://i184.photobucket.com/albums/x241/ryanvalin/Tundra/TundraStereo005.jpg

http://i184.photobucket.com/albums/x241/ryanvalin/Tundra/TundraStereo001-3.jpg

valin
05-28-2009, 07:28 PM
Also, the enclosure is downfiring, underneath the rear seats of my doublecab Tundra. I have 2 inches of clearance from max excursion to the floor. The magnets on the drivers are vented in the rear, and I have 1.25" of clearance from the magnet to the rear of the enclosure.

The subs are 12" Rockford Fosgate Power HX2's, running off of a Memphis Mojo MC-2000d, only set to about 1/2 gain, which would produce only about 500 watts per driver, and I can't turn the gain up anymore because the output does not increase.

Ellsworthz
05-28-2009, 07:33 PM
doesn't look to odd, iv seen about 100X more odd.

looks like a nicely built box to me. maybe your not used to the down firing?

snfsh79077
05-28-2009, 07:41 PM
what exactly is the odd sound? And just because your gain is set at half doesn't mean your not giving those subs more than 1000rms to the pair.

valin
05-28-2009, 07:43 PM
Perhaps that is it, but the output is very low, and I mean very low. I think it's pathetic. I just built a sealed enclosure for a 15" Rockford Fosgate Punch HX2 that I had laying around. It's 2.5 cubes, in the trunk of my Subaru WRX sedan, running off of an old BD1000a1, and it has 10 times the output. I expected the build in the Tundra with two 12 Power HX2's on 2000 watts to exceed the single 15" punch HX2 in the WRX on 1000 watts, which is in a truck. Know what i mean?

valin
05-28-2009, 07:44 PM
It rolls off hard on the lower notes, (yes, it is sealed, but it rolls off excessivly hard) and the bass just isn't clean, with very low output.

WrenchGuy
05-28-2009, 07:52 PM
Maybe its the pocket of air being compressed at the other end of the box?

I read briefly somewhere that having too long of an enclosure with drivers on one end can cause some issues.

Then I wondered about the floor standing tower type speakers so I don't know.

Just throwin it out there I guess.

mokedaddy
05-28-2009, 08:00 PM
There is a possibility of a loading problem but from looking at your design that does not appear to be the problem.

Have you checked to make sure both subs are in phase?

dumple
05-28-2009, 08:07 PM
Then I wondered about the floor standing tower type speakers so I don't know.

your floor standing speakers prolly have a port on the opposite end from the speakers

There is a possibility of a loading problem but from looking at your design that does not appear to be the problem.

Have you checked to make sure both subs are in phase?

this forsure

Volenti
05-28-2009, 08:55 PM
The enclosure is long enough to have standing waves effecting the response in the bass region, while this isn't directly altering the low bass it may be causing peaks in the response that make the low bass appear reduced in comparason.

I'd suggest packing the enclosure with roughly 3 pounds of dacron which will help to damp the standing waves, and see how it sounds after that.

mlstrass
05-28-2009, 09:24 PM
SSF not turned off or all the way down?

dillinja666
05-28-2009, 09:55 PM
i own one of those tundras...the carpet is nice and padded...might just be that its dampening everything too..

looking at the pic we have twin trucks...mines 4x4 too

valin
05-28-2009, 11:25 PM
The drivers are in phase. I am going to throw the enclosure on top of the seats so the subs are facing up, and see if that makes a difference. If not, I have an old box laying around that is 5 cubes. I'll throw them in that, wiht some boxes to cut down on some airspace and see how that works out.

If you guys heard this thing, you'd laugh. It's sad, at best. Mind you, I'm coming out of a system with two FI Audio 18" BTL's in 12.5 cubes at 32hz, but still, it's pathetic, even in comparison to the single 15 in the trunk of my WRX.

valin
05-28-2009, 11:25 PM
Keep the help coming guys.....I really do appreciate it.