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Discussion Starter #1
My car has factory speaker pods inside the doors. The 8" midbass drivers are pointed into the door, so the driver fires into the door rather than into the cabin of the car.

I'm about to install the door speakers, and will be deadening the doors, etc. I've read a lot about how sealing the door will improve midbass performance significantly and would like to try this also.

My question is, since the midbass drivers fire INTO the door, will sealing the door still improve bass/midbass response? Or would sealing the door (and breaking up waves inside the door by using foam/whatever) negatively impact the bass/midbass performance?

Thanks in advance for any advice/feedback/etc...
 

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Discussion Starter #3
Yep. The midbasses are mounted so that they point INTO the door, with the backs of the speakers facing into the cabin. Basically, they are inverted.
 

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With bass and mid-bass, inverting the driver should have no noticeable effect on sound quality, other than possibly hearing the motor more which could suck. It depends on the drivers of course.

As far as the other side, airspace is airspace, what you are doing when you seal the door is preventing the back wave from contacting the front wave of your speaker's output, thereby reducing cancellation. Also when you seal the door, you are creating a chamber for the speaker to work with in a cushioning effect. Most doors end up being IB, not sealed, but nonetheless a sealed door vs. an untreated door will be obviously better.

At higher frequencies, the cone shape plays an important role, but not at these lower ones.
 

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Speakers receive AC and move equally both direction regardless of frequency, treat the door exactly as you would if it were mounted traditionally.
 

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Discussion Starter #11
Sorry for the delayed response... just installed my head-unit and have been working like mad on that the last few days.

The car is a Mercedes SLK-350.

The speaker pods in the doors are made so that the 8" driver points into the door, and also requires a shallow-depth driver. I went with the Hertz Space 8 mids, as they seemed to offer the best performance for a shallow-mount midbass driver.

Also, the factory mids are run 180 off-phase I think. Not sure on that, but I've read it in a few places. Not sure how I would do that with the current setup, since my head-unit sees both door-mounted mids as one driver. I'll be upgrading the speakers this weekend or next, and will be using Hertz passive x-overs. Not sure if they allow me to run the drivers out of phase or not.
 

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Just put the positive on the negative terminal and negative on the positive terminal to wire them 180* out of phase.
 

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hi
Hello Something that to my me has worked is to put them in the doors in original montage and to use the package of Cascade for doors, this way you put him a bit of material for the front of the driver and put the damping pad stuck to the sheet of the door, with it I have had good results.

A tip that I pass to you is that if actually you do not want that the midbass pulls your soundstage towards the sides you must apply this formula:
speed of the sound in meters per second (340) / the distance in meters between the midbass = the result is the frequency to which you must cut the low pass in order that you do not meet affectedly the soundstage.
 

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Holy hell was that translated by monkeys?

You said something about deadening, then something about wavelengths.

The rest is lost in translation.
 

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Discussion Starter #16
Just put the positive on the negative terminal and negative on the positive terminal to wire them 180* out of phase.
Doh! I knew that. *smacks self in forehead*

I've been so wrapped up in the various processing features of my amp and head-unit that I forgot something I've known for years. Not sure how that happened. Perhaps I should stop licking my car battery's negative terminal to see if it's still charged.
:laugh:
 

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Discussion Starter #17
hi
Hello Something that to my me has worked is to put them in the doors in original montage and to use the package of Cascade for doors, this way you put him a bit of material for the front of the driver and put the damping pad stuck to the sheet of the door, with it I have had good results.

A tip that I pass to you is that if actually you do not want that the midbass pulls your soundstage towards the sides you must apply this formula:
speed of the sound in meters per second (340) / the distance in meters between the midbass = the result is the frequency to which you must cut the low pass in order that you do not meet affectedly the soundstage.

The formula you are trying to describe sounds interesting, but I don't really understand what you're saying.

Basically:

x = speed of sound (meters per sec)
y = distance between midbass and tweeter (in meters)
z = LPF cut-off frequency

x / y = z

Is that correct?
 

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My car has factory speaker pods inside the doors. The 8" midbass drivers are pointed into the door, so the driver fires into the door rather than into the cabin of the car.

I'm about to install the door speakers, and will be deadening the doors, etc. I've read a lot about how sealing the door will improve midbass performance significantly and would like to try this also.

My question is, since the midbass drivers fire INTO the door, will sealing the door still improve bass/midbass response? Or would sealing the door (and breaking up waves inside the door by using foam/whatever) negatively impact the bass/midbass performance?

Thanks in advance for any advice/feedback/etc...
Are the pods actual enclosures? If so, I don't think it would help dramatically... might make the whole assembly a better speaker cabinet and reduce panel vibration, but i's not gonna be like an IB driver coupled to the back of the door panel opening, which I am a big fan of...you probably already have that benefit. I would be curious if the enclsoure is too small and forces the Fs higher than it should.
 
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