Making car doors more like speaker enclosures

[JohnKuthe]

I just came up with an idea for a quick and dirty way to add metal panels over the big holes in the inner metal panels of my 2006 Grand Caravan's front doors!!

I bought some 1/16 inch thick double stick foam tape and I'm going to trace the two big holes (one above the 6/9 speaker and the big one towards the rear), cut a thin sheet of aluminum to fit (easy to work with) then form it and stick it on with the foam tape! Sheet metal inside the door is too thin for RivNuts or sheet metal screws without a steel insert as shown in two of the mounting holes in the 6x9 space anyway! Then my installer guy can stick the B-Quiet (like DynaMat) over it, holding them on even better! I may make little squares and rounds to stick over all the holes, then B-Quiet over it all! And of course m,y installer guy whose in charge (being paid for) of all the B-Quiet application will cover all metal panels inside and out before I stick on these aluminum sheep covers then B-Quiet over that!

Won't be extremely rigid like a real speaker cabinet but will be sort of airtight with the foam tape and the B-Quiet stuff stuck all over it! And can help but be better than the two gaping holes in there now!

I'm gonna take pics of the installation and post them here!

Click to read more...

 

[Umbra]

I just came up with an idea for a quick and dirty way to add metal panels over the big holes in the inner metal panels of my 2006 Grand Caravan's front doors!!

I bought some 1/16 inch thick double stick foam tape and I'm going to trace the two big holes (one above the 6/9 speaker and the big one towards the rear), cut a thin sheet of aluminum to fit (easy to work with) then form it and stick it on with the foam tape! Sheet metal inside the door is too thin for RivNuts or sheet metal screws without a steel insert as shown in two of the mounting holes in the 6x9 space anyway! Then my installer guy can stick the B-Quiet (like DynaMat) over it, holding them on even better! I may make little squares and rounds to stick over all the holes, then B-Quiet over it all! And of course m,y installer guy whose in charge (being paid for) of all the B-Quiet application will cover all metal panels inside and out before I stick on these aluminum sheep covers then B-Quiet over that!

Won't be extremely rigid like a real speaker cabinet but will be sort of airtight with the foam tape and the B-Quiet stuff stuck all over it! And can help but be better than the two gaping holes in there now!

I'm gonna take pics of the installation and post them here!

Hopefully the tape will hold up in the heat. The CLD over that should hold up to the heat so that might be enough once everything's together. However, I've used 3/4" self tapping sheet metal screws in three vehicles just fine.

If you really want to get into it you put the dampener on the outer panel to reduce panel resonance and increase midbass, then covered fiberglass insulation inside the door (avoiding the window) to absorb rear waves, then the aluminum panels with the dampener on them, more dampener around them on the larger parts, then a a decoupling layer probably closed-cell foam, then MLV (mass loaded vinyl) to keep outside noise out and the music in.

KHA's SQ build logs detail this extensively: http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/608637-2014-accord-sport-sq-build-keep_hope_alive.html

 

[350zspl 10+ year member]

XTC 6"x9" Speaker Baffles (5" depth) Protect your speakers at Crutchfield.com

 

[JohnKuthe]

XTC 6"x9" Speaker Baffles (5" depth) Protect your speakers at Crutchfield.com

Yep, gonna use Boom Mats on each speaker elements. An thanks for the suggestions (other poster) for the additional vibration and sound deadening but I'm gonna keep it pretty simple. Just B-Quiet (DynaMat similar) over all the internal; sheet metal, both sides, and these stick on aluminum panels. The darmed inner door sheet metal is WAY thin and I'd be very nervous about putting sheet metal screws into it. I mat, I will see.

John Kuthe...

 

[trumpet 5,000+ posts]

Yep, gonna use Boom Mats on each speaker elements. An thanks for the suggestions (other poster) for the additional vibration and sound deadening but I'm gonna keep it pretty simple. Just B-Quiet (DynaMat similar) over all the internal; sheet metal, both sides, and these stick on aluminum panels. The darmed inner door sheet metal is WAY thin and I'd be very nervous about putting sheet metal screws into it. I mat, I will see.
John Kuthe...

The additional steps shown by keep_hope_alive are very inexpensive, yet the benefits are obvious to the ear.

 

[LosIsATool 5,000+ posts]

Those little enclosures are to prevent water from getting in. You have to cut out the bottom. They are way to small otherwise, it will kill all midbass.

 

[JohnKuthe]

Those little enclosures are to prevent water from getting in. You have to cut out the bottom. They are way to small otherwise, it will kill all midbass.

Not really sure what you are talking about. "Little enclosures"? And cut out the bottom of what?

And "kill ALL (emphasis mine) the midbass"? What and how?

John Kuthe...

 

[LosIsATool 5,000+ posts]

Not really sure what you are talking about. "Little enclosures"? And cut out the bottom of what?
And "kill ALL (emphasis mine) the midbass"? What and how?

John Kuthe...

The foam cups.

And I mean kill midbass as in 80-300hz. You need airspace for that.

 

[Hertz Mafia]

Not really sure what you are talking about. "Little enclosures"? And cut out the bottom of what?
And "kill ALL (emphasis mine) the midbass"? What and how?

John Kuthe...

XTC 6"x9" Speaker Baffles (5" depth) Protect your speakers at Crutchfield.com

 

[JohnKuthe]

XTC 6"x9" Speaker Baffles (5" depth) Protect your speakers at Crutchfield.com

Yeah, I've got ordered four 3.5 inch deep AND 4.5 inch deep Boom Mats, gonna see which works the best on my Alpine SPR-69's which are:

3.5 inch deep should work pretty ideally!

John Kuthe...

 

[LosIsATool 5,000+ posts]

Yeah, I've got ordered four 3.5 inch deep AND 4.5 inch deep Boom Mats, gonna see which works the best on my Alpine SPR-69's which are:

3.5 inch deep should work pretty ideally!

John Kuthe...

Did you understand what I said? Unless you have leaky doors don't use them. It's a worthless gimmick that decreases sound reproduction. They are only large enough for a 3in wideband that only plays 300hz and up

 

[JohnKuthe]

Did you understand what I said? Unless you have leaky doors don't use them. It's a worthless gimmick that decreases sound reproduction. They are only large enough for a 3in wideband that only plays 300hz and up

Like everything else, opinions are all over the place! Some love them, others like you hate them!

Show me the DATA!! Objective data!!

John Kuthe...

 

[LosIsATool 5,000+ posts]

Like everything else, opinions are all over the place! Some love them, others like you hate them!
Show me the DATA!! Objective data!!

John Kuthe...

It's actually a simple concept that's not a opinion. Space makes bass. Low end reproduction requires airspace. A sealed door cavilty is what you need. Enough airspace to reproduce strong midbass and still create strong overall output into the upper midrange. Also they are flimsy which leads to cone break up. Like having 6x9s on the rear shelf with a woofer right under them. Non linear cone movement

 

[JohnKuthe]

It's actually a simple concept that's not a opinion. Space makes bass. Low end reproduction requires airspace. A sealed door cavilty is what you need. Enough airspace to reproduce strong midbass and still create strong overall output into the upper midrange. Also they are flimsy which leads to cone break up. Like having 6x9s on the rear shelf with a woofer right under them. Non linear cone movement

I'm an engineer, show me the DATA!! Frequency response curves, stuff like that!!

Oh, and for cone breakup, entropy is a constant!! It's GONNA happen!! Have a nice day!

John Kuthe...

 

[LosIsATool 5,000+ posts]

Sorry. I'm not going to run out and screw up my beautiful midbass to show you a RTA. The whole point of sealing the door is eleminating the back wave from combining with the front wave and adding mass which equals ridgitity

You don't need graphs for that