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I have always felt that the door environment for mid drivers was a as bad as it gets. I dont know how many times I have pulled drivers out of a door (especially in trucks) and they had gotten wet or were clearly exposed to high moisture levels and nasty dirty. Clearly dirt was getting into the VC, not to mention seeing warped cones and rotten surrounds.

I experimented in the mid 90s with building boxes in door panels and went as far as porting them (*just because I thought it was cool, but had no data, just made a port out of .5" PVC, you could feel air pump when they were really rolling!). One install in particular used to Boston Pro 5.25 in each door of an S15, and the drivers shared about .4cf.
The install sounded really good however I dont know if it was better *because of the boxed mids.....they likely sounded great otherwise.



I am about to install some Dyna MW 162 6.5" my truck. I would really like to do an install where I can forgo rigging the door with bracing, sticky goo foil (dynamat) and build a sealed or ported enclosure out of glass/mdf.
Or do CA drivers require an open back wave to sound good?

I have enough back clearance and can furr out the door panel to support the driver without interfering with the window assembly.


Is boxing a mid woofer a good idea, snake oil or other? Any sonic benefits or drawbacks? (clearly it would be a better environment for the back of the speaker)

Just wondering....


~JH
 

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I have wondered about this myself, there is very little info regarding the subject. put your drivers in winisd and play around with different box sizes and you will find that its hard to get enough air space inside of a door. For my two cadence 6.5" mids winisd shows about around 2ft is optimal for good response to about 90hz in a sealed box. so maybe IB is actually better then a tiny (probably .6ft max) box that would only respond good down to around 110hz. a small ported box is similar in that you really cant get enough space for them to extend very low but with a pretty big spike around 80-140hz which may not be bad. maybe a small sealed box with an aperiodic vent would do well. probably something you would just have to play with and tweak allot to get right.
 

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As you have found from WinISD, it is totally driver dependent. We run our midbass in 7 litres sealed, and the sound great.
 

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Enclosing your mids in a car is no different than what you would do for a sub or for home audio except that it would be highly favorable to know the car's transfer function ahead of time. When I say no different, I am referring to using the driver's thiele/small parameters to determine how it will be implemented or is it of any use.

Personally, I have considered this at one time and have stated several times to others that it should be pretty much be utilized with drivers requiring very small enclosures to be viable. This may rule out using most car audio drivers as they fair better IB as they were intended.

On the other hand you could use a driver that pretty much specs out to require ported only, but still have a beefy motor structure & xmax to withstand a sealed enclosure. The F3 will be rather high depending on what's your intended crossover point & the driver's Fs, but roll-off will be shallow. The same implementation the original Solobarics approached. Not a whole lot of drivers fit into that category from my searching.

Using a WT3 & Bassbox I did find some car audio drivers with a fairly high Q that were intended for drop-in IB installs that on paper would seem to benefit more from very small sealed than IB. These were drivers whose EBP was fairly high (close to 100). One particular I have is a Diamond 5.25" component set. Haven't gotten around to enclosing it, but it does sound rather wimpy IB & exhibits too much excursion even with a higher crossover point. I would expect less required excursion with more tonal control in it's lower range with a small sealed over IB of course.
 

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I'm going to be mounting a set of Quart QM100's in my kick panels,in small sealed enclosures. They will be crossed over at about 200 @24db/oct. With an x-over point that high,will being in a "box" make any difference? I'm just tired of hearing my Morels out of the front fenders and air intake vents.lol
 

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Even though those Quarts will be playing in the midrange area (200hz up) I would still insure that the space you provide them does not render a peaky response which could prove hard to EQ. That is something to always consider when enclosing any driver. Other than that I don't see the harm... I'd rather see small sealed drivers with plenty airspace behind them than larger drivers shoehorned just for the sake of being down in the kicks. If a person has a separate EQ to use on them then good, if not it WILL present problems.
 

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Thanks. My HU has "some" eq ability and I have a couple old AC EQT's,laying in the garage,but I'm trying for a very simple,6 speaker,6 channel system. I will endeavor to make the mid boxes as big as I can. Also,I'm not an SQ fanatic,just an old construction worker,who drives with the window down 75% of the time.
 

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I was referring to having a separate EQ when shoehorning drivers to tame the peakiness. With a small driver you should be okay, but I would still treat them as you would any other driver keeping them in the proper size cab. Even crossed up steeply some bleed through will still occur and you don't want to make harsh EQ adjustments that may affect other drivers above or below the Quarts range.
 
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