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2004 Rav4 JL900/5 HertzHDP-5 Rockford DSR-1 LPG26NA GS25 RS180-4 Um12
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Discussion Starter #1
Doing nice enclosures in the doors is looking like a lot of fabrication. There is a good location way up in the front footwells that would house 8” IB but the location is right next to the center counsel. The question is will this affect stage width? I’ve read some information about wanting to mount midbass wide like the rest of the front stage speakers. There’s also a decent spot in the footwells right in front of the seats next to the doors but I can only do 6.5 I think. I’m willing to do what is needed to achieve a good outcome.
 

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Ideally, keep them as wide as possible. Our localization of lower frequencies doesn't begin to diminish until about ~100Hz and below, where the lower frequencies become more and more omnidirectional. The difference in timing and phase, not so much amplitude, are more important for the perceived imaging of the midbass frequencies. This requires distance or separation of the two L & R sources in stereo.

In my daily driver install, I have the midbass drivers in modified OEM lower front door locations. The low bass images distinctly and widely all across the stage from far left to far right down to about 45Hz (i.e. the intro to Malia "Celestial Echo" as one example) even though my subwoofer is mono.

If your midbass drivers are mounted more narrowly in the vehicle (more towards the center), the width of the soundstage at those frequencies will mostly follow suit, as well as limited depth...i.e. an acoustic upright bass, electric bass guitar, or kick drum that is recorded or mixed so that it is deep in the soundstage and well behind the other performers in the band will not be perceived as deep in the soundstage as it should.

Here's an install by Peter S. at PSsound. I believe that there are more images and videos of the midbass build in PART 2 of the "MEGA MEGANE" videos and on his Facebook page.



Oh, and get your seat rails cleaned up and the rust removed then painted with a rust-preventative paint. Rust can quickly compromise iron and steel. You don't want your seat to break free in the event of an accident. I've seen this type of rust quite a bit in climates where they salt the roads during winter or just from the snow/moisture itself...also in tropical climates.
 

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2004 Rav4 JL900/5 HertzHDP-5 Rockford DSR-1 LPG26NA GS25 RS180-4 Um12
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Discussion Starter #4
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As can be seen I don’t have the room to build an enclosure along the bottom of the door like most I’ve seen. I’d have to build onto the stock speaker location and glass around inside sealing it. Then I would perhaps self tapping screw the glass enclosure to the door frame. Id rather cut the floor...
 

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Discussion Starter #5
Ideally, keep them as wide as possible. Our localization of lower frequencies doesn't begin to diminish until about ~100Hz and below, where the lower frequencies become more and more omnidirectional. The difference in timing and phase, not so much amplitude, are more important for the perceived imaging of the midbass frequencies. This requires distance or separation of the two L & R sources in stereo.

In my daily driver install, I have the midbass drivers in modified OEM lower front door locations. The low bass images distinctly and widely all across the stage from far left to far right down to about 45Hz (i.e. the intro to Malia "Celestial Echo" as one example) even though my subwoofer is mono.

If your midbass drivers are mounted more narrowly in the vehicle (more towards the center), the width of the soundstage at those frequencies will mostly follow suit, as well as limited depth...i.e. an acoustic upright bass, electric bass guitar, or kick drum that is recorded or mixed so that it is deep in the soundstage and well behind the other performers in the band.

Here's an install by Peter S. at PSsound. I believe that there are more images and videos of the midbass build in PART 2 of the "MEGA MEGANE" videos and on his Facebook page.



Oh, and get your seat rails cleaned up and the rust removed then painted with a rust-preventative paint. Rust can quickly compromise iron and steel. You don't want your seat to break free in the event of an accident. I've seen this type of rust quite a bit in climates where they salt the roads during winter or just from the snow/moisture itself...also in tropical climates.
Cars from NewJersey, I live in South Carolina. But yeah, good suggestion.
 

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As can be seen I don’t have the room to build an enclosure along the bottom of the door like most I’ve seen. I’d have to build onto the stock speaker location and glass around inside sealing it. Then I would perhaps self tapping screw the glass enclosure to the door frame. Id rather cut the floor...
Thats only true if you dont want to lose you "map pocket"...but who uses maps anymore anyways??

But seriously, if you dont mind losing that pocket and you are willing to handle the challenge of the build, there is ALOT of room there particularly if you build to the height of the switch panel.
 

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420TC, yeah, I wasn't suggesting to continue with installing the midbass in the doors, just suggesting that wider is generally better. I would avoid cutting the floor or compromising the area just beneath the brake and accelerator pedals for multiple reasons...potentially compromising the operation and safety of the vehicle, exposing the drivers to engine & exhaust heat, and wind/debris.

But seafish has a point regarding how the door enclosures could be built. Both options will require significant fabrication.
 

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Discussion Starter #8
Thats only true if you dont want to lose you "map pocket"...but who uses maps anymore anyways??

But seriously, if you dont mind losing that pocket and you are willing to handle the challenge of the build, there is ALOT of room there particularly if you build to the height of the switch panel.
just seems like a lot of curves to incorporate into the enclosure. The fabrications I’ve seen have straight lines to build up to. I think I could pull off the floor install much more professionally. If my test box shows decent phase behavior in the position by the side in front of the seats would that be worth pursuing?
 

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just seems like a lot of curves to incorporate into the enclosure. The fabrications I’ve seen have straight lines to build up to. I think I could pull off the floor install much more professionally. If my test box shows decent phase behavior in the position by the side in front of the seats would that be worth pursuing?
I diasgree with this statement...even if you used straight lines to make your box and mounted it on top of the existing door panel., there is still ALOT of room there from the bottom of the door to the height of the switch bezel. While a more rectilinear box might not look as sweet and as fiberglass ones incorporating curves and swoops etc, it would still look more then decent finished nicely in either vinyl or even carpet (easier to cover up mistakes LOL).
Furthermore, if you were willing to remove the parts of the vanity panel which are beneath the profile of the box you decide to make, you will gain even more volume from the added depth,

Of course, it's your car, your skills and your choice!!!
 

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Discussion Starter #10
The amount of time and work I have invested in my Audio build is absurd, relatively speaking . At the same time I have created a clean looking and nice sounding stereo system so far. When the midbass is figured and finished it will be a very respectable build overall, at least to mortal beings, some people on here of course are in a different universe. Whatever I do with the advice here, much attention to detail will be involved.
 

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Keep in mind everything in a car is a trade off.

What frequency range will the midbass play?

The center console results in a null, so the center of the pedals position will raise that null higher in frequency, likely far enough to be out of the range of the midbass in a three way

I think the stage pull in a that location is mainly from harmonics though, but you frequently can locate the midbass and hear pull in there.

If you read up on Opsodis, the wide midbass stage helps

One other thing to consider if you want it to look stock, you can likely fit four 3" to 4" woofers under the dash, there is often a surprising amount of room up there

It will get rid of the null while also minimizing the pull in on the stage. It is a crazy hard box to build though, especially if you don't' do fiberglass. The plus is it will be out of sight

There is often enough cabin gain to get away with the smaller woofers. You could probably fit four Dayton ND90 or 91s up there ported
 

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Discussion Starter #12
I have read some on Opsodis, I read the post by P Bateman a while back. Mounting the woofers close to 180* has been in the back of my mind for a while, especially how the wavelengths around midbass need to come from the sides for the ears to sense location cues, maybe depth, something makes mounting the woofers to the sides important. I’m not trying to fight good advice from more skilled members but that floor location by the seat is really seeming to be a good solution.
 

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Discussion Starter #13
Keep in mind everything in a car is a trade off.

What frequency range will the midbass play?

The center console results in a null, so the center of the pedals position will raise that null higher in frequency, likely far enough to be out of the range of the midbass in a three way

I think the stage pull in a that location is mainly from harmonics though, but you frequently can locate the midbass and hear pull in there.

If you read up on Opsodis, the wide midbass stage helps

One other thing to consider if you want it to look stock, you can likely fit four 3" to 4" woofers under the dash, there is often a surprising amount of room up there

It will get rid of the null while also minimizing the pull in on the stage. It is a crazy hard box to build though, especially if you don't' do fiberglass. The plus is it will be out of sight

There is often enough cabin gain to get away with the smaller woofers. You could probably fit four Dayton ND90 or 91s up there ported
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Here’s some phone rta measurements. The subwoofer is the UM12 true IB in the cargo area floor. I have eq’d it a little.
The midrange drivers are the Audiofrog GS25 in the sails, I haven’t eq’d at all. I’m very surprised that the right frog plays below 200hz.
 

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Discussion Starter #14 (Edited)
I know there’s plenty of information on tuning and I won’t be asking much about it unless something crazy, but I would be interested in where people would suggest crossover points here along with the actual install question. To see if my understanding is solid. I cut the floor and the subwoofer seems proper, I don’t expect to change after all it took. The GS25s are in beautiful sails with the lpg26na tweeters. Those sails took about 32-34 hours to get close to perfection, if something looks crazy in the response I wanna know but I really don’t want to have to change them.
 

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Discussion Starter #15 (Edited)
I copied and pasted this from a different post, I’ve had responses from different people on the different areas of the install.

I’m just think tanking ideas, I have gotten decent with fiberglass, perhaps a layer or two formed against the door metal under the door skin? If the inner door was braced and a glass shell was screwed on and sealed off, might that allow a standard door mounting keeping the stock look? This approach is well within my skill set, is non permanent and can be thickened with additional layers depending on what is needed and where. I think the curves and dips would add to the rigidity. If I wasn’t clear enough, a baffle that completely spans the entire door under the card.
 

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I don't know about the GS25, but lots of people are crossing the GB25 higher than the minimum recommendation, like 300-350 Hz or so. the GB25 is a pretty low distortion driver, but raising the crossover really lowers the distortion even more.

I would think similar would be a reasonable starting point. Practically any midbass should play that high without issues.
 

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First, I would invest in a measurement microphone with a known, flat frequency response, and one which also includes a calibration file.

For the money, a miniDSP UMIK-1 is hard to beat, and you can often find them used for a great deal as people upgrade to the just-released UMIK-2.


Otherwise, you may be chasing your tail and trying to correct for anomalies and limitations of your smartphone's internal microphone.

The UMIK-1 should still work with all of your smartphone and/or tablet apps via USB when combined with either the Apple CCK3 or an inexpensive USB OTG cable for Android devices.

In regards to your crossover choices, the inherent frequency response and parameters of the raw drivers that you chose should inform your decisions.

For the LP, where does beaming begin to occur, and at what point does the off-axis dispersion & response start to diverge substantially and unnaturally from its on-axis response?

For the HP, where is the Fs and where does the response on the low end naturally roll off, and how quickly?

Your chosen electrical crossover frequencies and slopes should result in the desired smooth and natural acoustical response (especially at the crossover region) that matches your target curve, while remaining well within each driver's inherent limitations on both the high and low end.

At least for the Audiofrog drivers, Andy has provided safe (and good) recommendations for the HP, LP, and slopes/orders.

You'll have to determine the best crossover points and slopes for your other drivers by analyzing the properties I mentioned above.

Deviating too far in either direction from the inherent limits of each driver will result in increased distortion and harshness, and/or reduced output potential.

The influence of the vehicle's interior on the response from each driver as derived from their particular mounting locations needs to be factored in as well...as you experienced with the low-end response of the right side GS25, and how it differs overall from the left side response.

The peaks and nulls in the midrange response (that deviate from the driver's actual nearfield FR) will be due to constructive & destructive interference (comb filtering) from reflections from the windshield, dash, and side windows, etc.

I think that the floor-mounted IB midbass drivers in the far left and right floorpan would work extremely well and would give you that ideal Left & Right separation.

The proper drivers would need to be chosen, especially in regards to your intended HP cutoff for the midbass...consider the Fs and Q parameters.

And cutting holes in the metal structure of the vehicle to the outside world has its own ramifications, as opposed to destroying or modifying replaceable door panels.

For door-mounted enclosures, I would build these as separate stand-alone units that mount to the door's metal structure via multiple riv-nuts/nut-serts.

The original upper section of the door panel can be cut along a natural horizontal line that interfaces smoothly with the pod containing the window rocker switches, etc.

You can build basic rectangular enclosures that span most of the length of the lower door, but could then be further shaped with add-on foam or MDF blocks, or reinforced FB filler "countours".

You can add a simple, narrow MDF baffle ring or "surround" on the outside of the enclosure where the driver will be mounted, and fill the outer edges and feather-out a smooth contour with filler out to the flat enclosure baffle to give it some "shape".

Cover the enclosure with matching carpet and/or vinyl.

For both fiberglass & MDF construction, provide plenty of internal bracing throughout to reduce flex and resonance. I'll typically use 1/2" hardwood dowels spaced out between the two large front and back panels. They are strong but don't take up too much internal volume.

Applying a full-coverage layer of 1/8"-1/4" CCF to the outer surface of the door skin or the back side of the enclosure will drastically reduce resonances in both the door & enclosure.

There are plenty of build logs showing door enclosure builds... Gary Summers' Mercedes and AudioGal's recent "Mid-bass experimental journey" come to mind.
 

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Well I took a bold move for my sq car... meet my new twins... Clarence and clary the clarus 10” in my life... one under each front seat

took a good few days to weld the chassis rail with a heavy 3mm wall box section to lower it 1.5cm, and then putting back strength I’d removed from across the car with 10mm laser cut steel baffles also, all neatly stitched into the car, it’s now stronger than it was before

I’ve literally just got the car back together after a few weeks off sorting it out...

finish on a pillar pods and enclosures to be decided as yet...

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positioning two midbass per side - I always prefer puting two drivers as close together as I can, because such mounted midbass drivers will act as one bigger unit, if you gonna use them higher into midrange that is also very positive to avoid some other issues.

Building sealed or ported panels is not too complicated, but you will need to do some brainstorming to come to a plan of how to execute install so everything will fall into its place when finished.

If you havent done such projects yet, I suggest that you maybe start with Aperiodic membranes first - you will need really small enclosure for that type of enclosure, you will have the least issues with making them looks like something..... Bass, upper bass and midranges will be very clean sounding with this kind of install - easy to do, easy to tune, speaker will have some protection against elements,.....
If you take a look at some of my doorpanel installs you might notice that not every doorpanel volume is stretched trough the whole lower part of doorpods,...in some cases enclosure is situated in place where original speaker is installed,everything else is just extended to make doorcards looks nice. For one 6,5" driver you will need approx 7-12 litre of volume, for dual midbass drivers twice of that, for ported enclosures for one 6,5 driver at least 10 litre....
Fact is that there is much more work envolved with such install, but for me, the end results are way better than with IB install
 

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Discussion Starter #20
I did a quick (3hour) experiment yesterday morning. I edited the thread “interesting results” with the details. The gist is that I molded a fiberglass panel across most of my left door. I have glass and material laying around in my shop so it was easy to do. I expected a little phase improvement, maybe at best but was completely blown away.
Hopefully you all might take a look at that post and give thought on the unexpectedly great response I obtained from the stock mounting.
 
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