Can you put ports in rear deck? Will it affect sound?

[badstang123 10+ year member]

If you take a look in the middle of my rear deck there are two rectangular areas cutout between the speaker holes. And then obviously a carpeted foam overlay sits on top of the deck when put back together. Since so much air is coming through I thought cutting into the overlay would allow more air from the trunk to come through into the cabin. This not only allowing more sound through but possibly reducing rattles from air being trapped in the trunk with nowhere to go.

My questions is if I make some sort of port that drops into the overlay and down to the bottom of the metal deck will this affect sound? We talk about port tuning on boxes all the time...but is there trunk tuning //content.invisioncic.com/y282845/emoticons/uhoh.gif.c07307dd22ee7e63e22fc8e9c614d1fd.gif//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif Or will it just let the air from the box pass through. I don't see it being a problem but I was curious about what some of you guys thought Here's a rough idea of what I plan on dropping through the deck. I figure this would be simple way of doing it.

Thanks,

Justin

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[germanyt 10+ year member]

I've heard of porting thorought the rear deck before. It is my understanding that people build the box so the woofers fire up or back and the ports extend from the top of the box to the holes in the rear deck causing the air to hit the back glass and go forward. Don't know how this would sound and I could be wrong but it would seem that this would almost make your trunk car into a hatchback. By that I mean that the bass is going straight up into the glass and forward rather than to the back of the trunk first.

 

[Twistid 5,000+ posts]

rear decks are for women and small children, just cut that bish out //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[GCAdidas13 10+ year member]

well one general rule of sub boxes is that the port and sub should be on the same plane. if you were to do anything but put the subs in so they fire through the rear deck, it will probably have some serious cancellation. if you really want to give this a try, you might have good results if you put the subs firing forward with your back seats down and the port through the rear deck

btw- i had a 1995 camry that i cut the entire rear deck out of to make room for two avalanche 15's sealed, but i didnt get a decent listen before i got rid of the car

 

[GCAdidas13 10+ year member]

after reading your whole post instead of some of it, i'd like to add this:

if you are talking about a port completely separate from your subwoofer box, it will do little to no good

 

[reneeb7363 10+ year member]

Ya beat me to it adidas! LOL!

I would be concerned about cancellation--- like when you face your sub forward in a trunk and the "echo" waves cancel the primary freq from the sub.

we need to get some of the pro's in here to know for sure.

 

[Twistid 5,000+ posts]

I would be concerned about cancellation--- like when you face your sub forward in a trunk and the "echo" waves cancel the primary freq from the sub.
we need to get some of the pro's in here to know for sure.

//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

 

[reneeb7363 10+ year member]

lol twisted.... face your sub forward in a NON sealed trunk.. youll see what I mean

 

[Twistid 5,000+ posts]

lol twisted.... face your sub forward in a NON sealed trunk.. youll see what I mean

i have, although i noticed a slight decrease in output there was a significant increase in low-end and almost 50% reduction in rattles... but i dont see how facing your subs foward would cause

"the "echo" waves to cancel the primary freq"

 

[saywhat? 5,000+ posts]

it was louder with my type r that way, than firing rearward...

 

[937DYTBOI 5,000+ posts]

this is coming clear to me im wanting to do the same thing

 

[reneeb7363 10+ year member]

dont laugh... I dont have my adobe photoshop at work to illustrate this-- but this is how it was drawn out for me.

basically the pink wave is the delayed "echo" if you will. Because of the delay, in most vehicles, the sine wave acts in opposition thusly cancelling out (partially) the initial output from the sub that is facing forward. Have ya seen the ads in airports, etc, for headphones that cancel surrounding noise...they work almost exactly the same way by cancelling the input sound by creating an exact opposite sine wave.

 

[xclusiv3 10+ year member]

i faced my subs forward and there is hardly any trunk rattle.

mine isnt completely sealed off

theres about an inch gap from top of my box to bottom of the rear deck

and the panel in the back has little gaps on the corners that allowed air to get by and caused a little rattle, but i stuck a towel in them and rattle is gone.

i dont know how itd be if i faced it to the rear but with the mags the rattle would be incredible but i hear it would be louder.

i was going to try to get mine 'foamed in' but i was told the gaps on the panel in the back arent big enough and worth the mess.

 

[937DYTBOI 5,000+ posts]

i just want my stuff to hammer when i get it installed, i figured facing them forward and porting the box straight into the deck would do me great but i guess it really depends on the vehicle

 

[reneeb7363 10+ year member]

I hear ya... i tried many different locations/directions for my (now dead) JL. facing directly backwards sounded no better than one little 8 in free air (I drive a 92 prelude) Facing the sub to the rear my 12w4 really works it! Trunk rattles like crazy but half the fun is eliminating the rattles right?