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boddy
09-22-2011, 03:44 PM
My car has a sort of plastic basket behind the speaker, but with big gaps in it. I was thinking if i get some sound deadening material and layer the basket and lay it over the gaps with a little hole for the speaker wire i will have a nice cosy enclosure for them, how would it sound?

This is what it looks like, minus the wood spacer.

http://i287.photobucket.com/albums/ll122/greenalex90/baffles009.jpg

kushy_dreams
09-22-2011, 03:48 PM
Most door speakers are intended to be ran free air. What you are looking at is a baffle to protect the speaker from moisture.

TheUnderFighter
09-22-2011, 03:48 PM
That'd make a nice little enclosure for the speakers. Assuming that it wouldn't be too small for the speaker, you could always try it out!

boddy
09-24-2011, 01:15 PM
I'll get some sound deadening and try it next weekend, how will it actually improve it if it does?

Moble Enclosurs
09-24-2011, 02:51 PM
I'll get some sound deadening and try it next weekend, how will it actually improve it if it does?

It might actually hurt the sound, unless your door panels and doors interior are not sealed up anyhow. The reason is, this space will cause the lower frequencies of the mids, around 60-120Hz, to suffer. unlike larger areas, such as that of the actual door volume, which can virtually be called an IB. This allows for proper operation of the driver, not necessarily in free-air, but with enough compression area to keep the driver from being mechanically limited to reproduce the lower response range. So, limiting this compression area will likely affect vocals and realism in the sound, but will be accommodated by resonances in the vehicle anyhow. Unless the drivers are designed for small compression operation, like that of bookshelf type drivers with small excursion capabilities and low BL factors. But nothing is not worth trying in my mind. :)


But as an improvement, it may help timing alignment and phase differences from the partially attenuated rear wave resonances that you will normally encounter in a traditional "door" speaker. :) This will overall create likely a more "solid" output.

wenn_du_weinst
09-24-2011, 02:57 PM
You do not want any of the rear wave coming into contact with the front wave. You want the door 100% sealed doors. Anything you let leak through will muddy the sound. Free air is another word for infinite baffle, not playing with both waves combining. I even seal the door panel around the mid so only the waves go out the front and not inside the panel

wenn_du_weinst
09-24-2011, 03:04 PM
you guys read that wrong
it has a plastic elevated baffle so it's not mounted directly on the door skin. Many factory cars do this to get more mounting depth. The ones on his car are vented, he was wondering if he should seal those, the answer is yes.

Moble Enclosurs
09-24-2011, 03:09 PM
You do not want any of the rear wave coming into contact with the front wave. You want the door 100% sealed doors. Anything you let leak through will muddy the sound. Free air is another word for infinite baffle, not playing with both waves combining. I even seal the door panel around the mid so only the waves go out the front and not inside the panel

Very important to know! Good point.
Now, free-air may be used as a forum terminology for IB, but they are actually two different things in testing audio. Free air does not separate the front and rear wave in testing, but IB does only on a single plane. The door area is not on a single plane, so an actual IB does not exist.... just a very large compression area with leaks(unless fixed from factory settings). But, free-air, which is used to test a drivers limitations, do not separate any sound waves with a plane at all. In use of the driver, within a car, really nothing is real IB as even the car interior is considered a compression. But for small enough drivers in the higher frequency ranges, this can be considered a virtual IB setup. So, I know what you mean by they are the same thing. But for actually designing an area for proper operation, they should be separated in their meanings because the IB primarily relies on back wave resonance at that point, in which if a door is to be sealed, it will exist. It is just then, a very large sealed compression area, lol.
Meant to say that it does this to control it. lol

wenn_du_weinst
09-24-2011, 03:24 PM
It's also important to note that in old school terminology, Infinite baffle was a large sealed enclosure. The baffle was ''infinitely'' wrapped around the rear wave making it impossible for the 2 to combine or cancel out. The problem with doors as an enclosure is they flex, they have leaks, they have wires window parts, ect ect. There is no real way to make a car sound like a HT system. It's true a 6.5'' driver will not visibly flex a properly deadened door, but it will do it enough to muddy the response of the driver. Then you have the problem that most door panels are not directly on the door skin and there is usually a gap, even when this gap is sealed off you can not get around the diffraction problem like you could in home theater systems.

Moble Enclosurs
09-24-2011, 03:26 PM
you guys read that wrong
it has a plastic elevated baffle so it's not mounted directly on the door skin. Many factory cars do this to get more mounting depth. The ones on his car are vented, he was wondering if he should seal those, the answer is yes.

I read it correctly, and it clearly shows that in the picture of what you are saying, yes. The sealing of the area of concern, again, as I stated would create good and bad effects, such as first increasing the low end response limitations for a decrease in output around 60-120Hz, but also increasing the tonality of the driver from a virtual IB setup and control excursion a bit more accurately, which in turn can also increase output in the enclosures operating range thereafter.

Moble Enclosurs
09-24-2011, 03:40 PM
It's also important to note that in old school terminology, Infinite baffle was a large sealed enclosure. The baffle was ''infinitely'' wrapped around the rear wave making it impossible for the 2 to combine or cancel out. The problem with doors as an enclosure is they flex, they have leaks, they have wires window parts, ect ect. There is no real way to make a car sound like a HT system. It's true a 6.5'' driver will not visibly flex a properly deadened door, but it will do it enough to muddy the response of the driver. Then you have the problem that most door panels are not directly on the door skin and there is usually a gap, even when this gap is sealed off you can not get around the diffraction problem like you could in home theater systems.

Yes. I was referring to the difference between that an free-air, not the definition of IB. But what I meant was, if it were not completely sealed, then the IB would be more of a means of a passive radiation per-say, than a solid IB. So, unless this is controlled as we have mentioned, then the IB will not really exist, and those resonances of the materials will need to be accounted for. We are saying the same thing, lol.

Moble Enclosurs
09-24-2011, 03:41 PM
And what I meant by it relies on back wave resonance, is that is has to control it completely to exist. Sorry if I worded that a little different. :)

wenn_du_weinst
09-24-2011, 07:59 PM
there was no pic for me before. I'd cut the stupid basket thing off and seal the holes infront of the cone

Moble Enclosurs
09-24-2011, 10:35 PM
Yea, and make sure the door is sealed great as well, and you should be fine that way. I ended up making fiberglass enclosures completely seperate of the door chambers that are on the door panels, that way I do not have to worry about in-door resonances as much. Works extremely well! Very well defined midrange response all the way down to 53Hz! A properly sealed area will do wonders for any driver location, and a poorly one will ruin everything.

Kangaroux
09-24-2011, 10:37 PM
keep_hope_alive's build log has a very nice example of how to seal off and waterproof your speakers.

Moble Enclosurs
09-24-2011, 11:43 PM
That is true. I have looked at is as well, and though it looks like it has cost quite a bit and taken a LOT of time, It seems well worth it......great to look at for inspiration for anyone wanting to better seal their vehicle. i will second this. They did a great job.

Jroo
09-27-2011, 03:20 PM
I do know a guy that took those XTC baffles to block water and used those to make sealed pods. He put fiberglass resin to stiffen them up and said they worked well. I have no idea what the airspace ended up being, but he did use a larger XTC baffle than his speaker was.