Sealed enclosers: How big is to big?

[Morphes 10+ year member]

Hello, i have a 05 passat and i was thinking of creating a subwoofer box for my 2 9500's (mtx 10"), my plan was to make a box that fills up the rear space then a plexiglass grill hiding the subwoofers. So it goes in this order:

/Seats/sub box---about 2 feet--- Sheet of plexiglass with holes in it for the sub.

My question is, if i build a box around the car will it affect sound in a negitive way to have more cubic feet than recomended by MTX? Also i was planning on building it at an angle so it go with the angle of the seats, will this create a negitive sound quality? Furthermore will the Sheet of plexi with hols in it create a negitive effect?

Thank you all so much for your time, i really appreciate the kindness of this forum and how helpful each and everyone of you are.

-Morphes

::EDIT::

Will i need any stuffing in the subwoofer boxes, like polyfill or anything similar?

Click to read more...

 

[JimJ 5,000+ posts]

"Too big" is a little vague, but as long as you stay under 4 times Vas, you avoid the driver acting like it's in an infinite baffle setup. I'm not sure that MTX would be a good candidate for IB. Going with a very large enclosure is going to drop the Qtc, improve low end response, improve transient response - and lower overall output.

If you're concerned about it, you could always put things inside the box to take up internal volume.

 

[Trixter 10+ year member]

it would also depend on how much power your putting to it. the more power the less box and the more box the less power. the angle or the plexi will not effect the sound quality. the plexi may block it a fraction....but that depends on how big the holes are and how many. (kinda like having the back seat up or down...but probably not even that much because the plexi is thiner and doesn't have padding to absorb it.)

 

[Morphes 10+ year member]

Just curious, i already have a box built thats ported, however i couldnt fit two of them back there so what would it sound like if i had one sealed and the other ported? would i get best of both worlds or would one over power the other?

 

[Trixter 10+ year member]

you may get cancelation. usually not a good idea to mix box types in a single system. the only way to safely do it is if you tune the boxs differently so the have different x-over points. some people do this but usually with a band pass box involved because they have a narrow sound range and the have another box pick up where it leaves off.

 

[Morphes 10+ year member]

Thank you so much for your help Trixter and jimj, this has really helped me alot in my next design. I will post pics once i start doing it.

Thank you again

 

[Trixter 10+ year member]

np...just remember the pics!!