So say you have 2 12" subs in a box in the trunk and you don't use these to cover the 6x9'*, will it DAMAGE the speakers at all, or will it just sound bad? I think I'll end up doing this, but I'm just curious.

Actually...

I've seen some pretty bad damage done to the surrounds
from a sub beating. This also effects the coils since they
are also pulled to their extremes of travel.

I imagine some inferrior components would fail quickly
if your sub box moves a lot of air.

When the bass note hits.... and the mains are crossed
as full range and likely the "bass bost" function is on...
the driver is about already at full extension then add
the additional pressure from the box, you get the idea.

The sound is really beyond a thud or pop its very
noticable (i was so desperate I peel & sealed my
speaker baskets) which as a side note did not hold
up well and still need re-done.

Really this is about the only benefit to the "pass thru"
except moving a few 2x4'* it helps to keep it open
to allow someplace for the air to escape. It'* a trade
off 'tho since the boxes will hit better in an enclosed
space.

Have you ever heard a properly ported enclosure with one 12" ?

yes, you can damage speakers, that is the simple answer. My stockers pop all the time, BUT IMO, a good aftermarket speaker will not have this problem because they will be able to "hold their own" and not have the sub(*) move the cone

Ok, thanks. And sorry for being naive, when you say "peel and seal" do you pretty much mean using double sided adhesive tape to apply the containers over the speakers?

And my box for the 12s is not ported. What is really the difference between ported and unported in terms of sound quality?

peal and seal is a home heating duct insulator. can be found at home depot


the sound difference is that ported boxes are normally "boomier" where sealed boxes normally have tighter bass

Thanks Rob. I'll have to test out the subs and see how I like them with a closed box. I can say that I want 'tight' precise bass, not a lot of distortion, but as long as I get some good resonating bass.

good subs in sealed boxes can still rattle whole cars.

I'm aware of that. And I'll be taking steps to keep the rattle down as much as possible. As far as porting sub boxes goes, what is a "properly" ported box? What determines the sizes of the holes? And where?

there are full formulas and stuff to calculate port length, area, volume, and other stuff.
Google it, its actually quite a process. You normally tune a box to specific frequencies too.

want to come stop the rattling on my car too? It can be your test vehicle.