Finally doing it right - need some input

[LongThrow]

Doors or rear deck?
If you really are asking about the rear door speaker holes, it honestly doesn't matter if those are sealed or open.

****, typo again.

REAR DECK HOLES

 

[audioholic 5,000+ posts]

No, I personally don't run rear fill. We are still talking about the holes. Should I seal off the holes, leave one open, or leave both open?
original question -

So in terms of SPL or Sq respectively, should I seal up the rear deck speaker mount holes? Or leave them open?

IMO the best solution would be to open the holes up larger, or perforate the rear deck with many small holes. That is, if you value your fidelity enough to do such a thing. most 'enthusiasts' just pop the rear speakers out and call it awesome.

In terms of SPL, you will get a more peaky response with the bandpass effect, but there is no guarantee what freq range would be affected. For a true purpose-built SPL rig, it would be better to eliminate unknown variables such as that, and tailor the enclosure/speaker/cabin to achieve the response you want.

For SQ, sealing the holes means all the output from the sub system will have to filter through your rear seat before reaching the passenger compartment, which would affect freq response. But leaving the holes open *might* can such a spike in freq response that it sound even worse.

Its really impossible for me to say what is best in your specific situation. Planning is great and all, but sometimes you face a situation with so many variables, that its simply easiest to use trial and error. Leave the holes open, if you are happy with it, great. If not, seal the holes up with something you can remove (screw boards over the holes for example). If sealed doesn't satisfy you either, remove the boards and open the holes larger (or add more holes like I suggested above).

 

[adulbrich 5,000+ posts]

I say remove the plastic rear deck all together. You can just put it back in if you go to sell the car later, instead of having a bunch of holes in it. Would be better anyways

 

[audioholic 5,000+ posts]

Im not familiar with the vehicle. If the rear parcel shelf is removable, by all means take it out. But usually those shelves are structural and you have to worry about weakening the body if you remove too much. But Im use to metal parcel shelves too, so idk how much structure a plastic one is adding.

 

[adulbrich 5,000+ posts]

I'm used to metal cross-braces with large spaces in between that are covered by a plastic or carpeted fiberboard rear deck