liv2ride

iTrader: (1)

Here are some pictures of my Idea to make a vented box with a connected funnel that will hopefully transfer most the waves into the cabin, and not let any enter the trunk (badd vibration in the trunk ) The box hasn't been built yet, but I know for a fact that the trunk and the mirror have BADD raddling .. and I don't feel like wasting my money on dynamat if i can eliminate the waves int he trunk by transfering them in the cabing with this funnel.

So my question is:

Will the funnel (when sealed with the actual box) cause a big alteration in the tuning frequency of my box design ?

I hope I can get some Feedback on these photos and prototypes..

Creamedweasel

From what I see, if you can make the funnel less wide that would be better. Not the opening but the part the covers the box. Just use simple geometry to calculate where the waves will be bouncing off that surface. Best of luck though. I hope it works out.

20Sunfire05

iTrader: (1)

Sealing a chamber on the front of your bax like that may cause it to behave like a bandpass. But I have never seen a bandpass ported into the other chamber.

dogstar

iTrader: (2)

just spend some money on sound deadening.
there are less expensive alternatives to dynamat that work just as well, and your trunk is still going to rattle even with a funnel.

for what its worth, i dont think your funnel will work very well, or itll sound strange, but give it a try.

liv2ride

iTrader: (1)

Damn, I thought It would def be a good idea.. Friend of mine told me to invest in some cheap walmart deadening, and just layer the hsit out of it on the trunk lid.. mayb i'll end up that route .. but another question, would the funnel type idea make the bass louder in the cabin, versus just having the box in the trunk like that ?.. or no..

At least I had fun drawing up that sub for that box lol.. haha.. okidokie

Oh damn, another question.. will the box sound good with two ports on each side ?.. or should i just put the subwoofer more to the left or right, and put a wider port on the opposite end ?

Dukk

It IS a good idea. Yes it's a bandpass but no big deal there - just design it as one and you're good to go.

Bandpass gets a bad rap IMO..

zzzzzzz

iTrader: (5)

http://www.the12volt.com/caraudio/boxes4.asp
isobaric 3 chamber single reflex bandpass enclosure is what i would do and port it in car
http://www.roadfly.com/bmw/gallery/picture.php?path=26170,1;26165,1;-64,6;

liv2ride

iTrader: (1)

Thanks for the excellent feedback and the good ideas.. I probably won't end up doing the funnel now, cuz I have a feeling it'll play around the the tuning frequency, but I will probably end up putting some sound deadening on the trunk lid..

20Sunfire05

iTrader: (1)

I like my bandpass, no one believes me when I tell them I only have one 10".




b-quiet.com seems to have some reasonable prices, much better than what I paid for a dynamat extreme trunk kit. Plus they are Canadian based.

Nathan Siy

It really depends on how much surface area is on that ski hole / pass through thingy. If you can open it up large enough to equal the piston's area and port area, it should act the same as in a normal trunk application.

If it's much smaller, then your going into a hit or miss zone, creating a BP enclosure with a port length of 3/4" (or whatever the thickness of your wood funnel is) and could tune things unpredictably.


I've had some good experiences with rear firing the woofer, but front firing the port.


The other alternative is to seal off your front baffle to your trunk. Then, theoretically, nothing gets into the trunk.