Project: Best sound stage possible WITHOUT kick pods!

[tekdeus]

Midrange speakers and tweeters are very directional, so for this project I wanted to get the best stereo imaging possible, without cumbersome kick pods at my feet. This means to have the speakers as far forward as possible, and facing my ears as much as possible with minimal interference. The gear is 5 1/4" MB Quart QM130 midrange speakers and A/D/S PX soft dome tweeters with an A/D/S crossover. These components have won many sound quality competitions in their day.

I chose to pick up a set of 91-92 door panels with the much larger speaker grill opening. I cut out 1/4" MDF wood rings to mount the speakers to, then hot glued 1/4" dowel rod to set the angle of the ring. I then hot glued grill cloth to create the shape for the fiberglass which I then laid, with 2-3 layers.

On the driver's side, I trimmed the grill, wood ring and the speaker basket to have the speaker sit as far out as possible, with maximum angle facing the driver's seat. I used some foam to fill the gap that this caused. The passenger side needed much less angle, and faces the driver seat more easily. I had to bend and trim some of the metal of the door, but nothing major.

The key with an install like this, is to have the speaker airtight to the door panel, so the door itself becomes the enclosure. I have the same door speakers in my MK2, and they sound phenomenal if you put your head in the center of the car, but the stereo imaging gets lost when sitting normally. I will mount the A/D/S tweeters on the kick panels, which should nicely polish off the stereo soundstage! I will let you know how it sounds when its done!

Driver's side:

Passenger side:

I almost had a clearance issue with the window, but got away with it!

 

[rtrdpenguin]

Wow, with the cover on it looks 100% stock!

 

[Pernilongo]

this is the best speaker install design in a supra hands down. I've been thinking how do this kind of install without the space between the speaker and door panel for like 4 years now and never arrived at anything--- this is witty. the closesest i came to smth like this is to install 4" into 100% sealed stock box and insulating the gap with the door and installing 5 1/2 mids in the lower parts of the door and then insulating the space behind them with combination foam to prevent sound leaks and trick the speaker into working with space as close to vas as possible creating a 3 way system. I think your design deserves some kind of recongition here. Although i do think soundstage is something more complicated then just speaker positioning.

I think imaging is more what your are talking about.

 

[Chris86.5]

good job... if i could i would shake your hand because i havent really seen anyone do this kind of thing in a supra... though i would go for a 6.5" speaker personally i like what you did.

 

[pbasil1]

Looks good, but how can you insure that the speaker gest sealed to the actual door? And have fun sealing the doors them selves, i sure strugled with it and still know that there are leaks, plus we have the problem of too large an enclosure for the 6.5" mids... You certainly were witty and inovative, but i still think there are flaws.

By no means am i trying to put your work down, it looks great and will definitely sound much better than if you were to simply drop the same speakers in the stock mounts. But i feel these supras have much more room for improvement... Especially in creating a smaller enclosure for the mid.

Perhaps for the tweeter you could place them just in front and under the mid. Like on the carpeted part of the door panel? Or there is always the option to place them in pods on the pillars if you dont have a gauge cluster on the drivers side...

Here is how mine turned out...

 

[Pernilongo]

Looks good, but how can you insure that the speaker gest sealed to the actual door? And have fun sealing the doors them selves, i sure strugled with it and still know that there are leaks, plus we have the problem of too large an enclosure for the 6.5" mids... You certainly were witty and inovative, but i still think there are flaws.

By no means am i trying to put your work down, it looks great and will definitely sound much better than if you were to simply drop the same speakers in the stock mounts. But i feel these supras have much more room for improvement... Especially in creating a smaller enclosure for the mid.

Perhaps for the tweeter you could place them just in front and under the mid. Like on the carpeted part of the door panel? Or there is always the option to place them in pods on the pillars if you dont have a gauge cluster on the drivers side...

Here is how mine turned out...

Pbasil1, I think that your install is perfect from the technical execution point of view. The level of your skill is very high as well as understanding of source of good sound. Nevertheless, and by no means i want to sound sharp, the original install of this thread has clear engineering advantages. Not on a technical level, but rather on proper design. Heres why.

No, you can not ensure that the speaker will get sealed to the door in free air install. The concepts of "free air" and "sealed" are contradictory. However, his install is more air-tight compared to your type. First of all, as far as i know you have ensured that the thin metal part of the door you mounted the speakers to is completely sealed by anti vibration material. this prevents sound waves from the back of the speaker not to cancel the ones that come from the front of the cone. car audio 101. well done. Then you have put some of that blue stuff behind the speaker ( sound deadening?) to absorb the energy. There is also a huge hole in the door for the window to come up and down. And its right on top of the back of your speaker. Since there is no foam or some sort of soft material to absorb and cancel the sound waves its safe to assume that they bounce off the blue stuff get mixed with road noise thru exterior panel vibration and exit thru the the window opening. Also, you have all that space between the speaker cone and the panel. your speaker is too large and some of its surface is firing into the panels pocket. When you put on the grille and restrict the air movement i think it goes right into that space between the plastic and metal part of the door. Maybe creating turbulence of some kind?

His install is devoid of these problems.

1. The space between the panel and the 1st layer of metal can be completely sealed by blocking heater duct, putting weather striping around the edges of the door and so on. There is no hole on top on the panel and first layer of metal, like between the first layer of metal and second.If the speaker is shallow enough you can also block the stock speaker opening to prevent it from leaking into the space between the metal parts. I don't think thats the case with his install though.
2. he doesn't have all that space between the cone and panel. If you make it pretty enough you don't even need the grille.


Finally I'm not saying that his system will sound better than yours or mine, maybe no one will ever notice the difference at all. But from the design point of view i think he presented the best thing in speaker placement in supra car audio section on this forum. No its not done 100% perfect, but its very creative. And i think we are taking about the perfect design here instead of competing whose system sounds better.

In June issue of car audio and electronics on page 50 or 52 they have a pretty good simple fiberglass box design that will work very well in out cars if placed instead of the carpeted part of the door. That would be the perfect sealed application in out cars. I don't have the resources or time to do it.

P.S.

If i sounded like i want to argue with you i apologize, that was not my intent. I simply wanted to discuss car audio issues respectfully and impartially.

Respect.

 

[tekdeus]

Yes, perhaps the perfect install would be airtight enclosed fiberglass pods to the spec of the door speaker. But in my experience, mids that are airtight to the panel itself and use the door volume to resonate within, produce a nice full sound. I will be crossing my mids over steeply so nothing below 160hz will pass through them anyhow.

Good looking 6.5's! See if you can find some dense foam to seal up the gaps between it and the door panel. Do it to one speaker first, then use your balance controll to listen to it compared to the other one as it is. You might be quite surprised how much better it is

 

[pbasil1]

Pbasil1, I think that your install is perfect from the technical execution point of view. The level of your skill is very high as well as understanding of source of good sound. Nevertheless, and by no means i want to sound sharp, the original install of this thread has clear engineering advantages. Not on a technical level, but rather on proper design. Heres why.

No, you can not ensure that the speaker will get sealed to the door in free air install. The concepts of "free air" and "sealed" are contradictory. However, his install is more air-tight compared to your type. First of all, as far as i know you have ensured that the thin metal part of the door you mounted the speakers to is completely sealed by anti vibration material. this prevents sound waves from the back of the speaker not to cancel the ones that come from the front of the cone. car audio 101. well done. Then you have put some of that blue stuff behind the speaker ( sound deadening?) to absorb the energy. There is also a huge hole in the door for the window to come up and down. And its right on top of the back of your speaker. Since there is no foam or some sort of soft material to absorb and cancel the sound waves its safe to assume that they bounce off the blue stuff get mixed with road noise thru exterior panel vibration and exit thru the the window opening. Also, you have all that space between the speaker cone and the panel. your speaker is too large and some of its surface is firing into the panels pocket. When you put on the grille and restrict the air movement i think it goes right into that space between the plastic and metal part of the door. Maybe creating turbulence of some kind?

His install is devoid of these problems.

1. The space between the panel and the 1st layer of metal can be completely sealed by blocking heater duct, putting weather striping around the edges of the door and so on. There is no hole on top on the panel and first layer of metal, like between the first layer of metal and second.If the speaker is shallow enough you can also block the stock speaker opening to prevent it from leaking into the space between the metal parts. I don't think thats the case with his install though.
2. he doesn't have all that space between the cone and panel. If you make it pretty enough you don't even need the grille.


Finally I'm not saying that his system will sound better than yours or mine, maybe no one will ever notice the difference at all. But from the design point of view i think he presented the best thing in speaker placement in supra car audio section on this forum. No its not done 100% perfect, but its very creative. And i think we are taking about the perfect design here instead of competing whose system sounds better.

In June issue of car audio and electronics on page 50 or 52 they have a pretty good simple fiberglass box design that will work very well in out cars if placed instead of the carpeted part of the door. That would be the perfect sealed application in out cars. I don't have the resources or time to do it.

P.S.

If i sounded like i want to argue with you i apologize, that was not my intent. I simply wanted to discuss car audio issues respectfully and impartially.

Respect.

Oh by no means am i taking this as an insult or start of an argument. I simply didnt see how the rear of the speaker was going to be sealed in the door. But now you clarified. Perhaps i spoke too soon and should have analyzed the install a bit better.

You are correct in the statement that my mids are too big for the door. I wanted to make a statement with my install. Never have i EVER seen such a large 6.5" mid in my life. And quite frankly they dont get much bigger! Technically these are measured as 6.75" mids, but can be used in custom 7" applications. The basket its self didnt even come close to fitting in the factory speaker pod. Thus, i had to fab a new bracked out of 2 layers of 3/4" mdf, and an extra 1/2" mdf spacer just to enable the window to still roll down.

I have seen on other cars the utilization of the carpeted pocket part of the door, and some day after my car is rebuilt and i get back to the stereo i plan to build a fiberglass enclosure for the door and these same mids to really get it all right.

I appreciate your un biased statements. Its great to have someone who is actually knowledgeable comment on my install, even though some of it may be negative. Im very used to dealing with a cheap kid who thinks that a good system has to have 2 15" subs and 4 tweeters just to sound good....

 

[Supra469]

I'm loving what you guys are doing.......I too have some MBQuarts to install. Wanna see the final install to get some ideas of how to mount mine.

 

[applesauce]

I got some Pioneer comps. in the oem 6.5 mounts. I did this a while ago... nothing like those custom moldings, thats 100% hotness...

They sound great might i add, along w/ my oem sub...

 

[NashMan]

you must have cut alot of the door away away i was thinking done this befor as in clock the speaker towords me but i shyed away from cutting the door caus ei did not wana risk cuting nice hole and my speakers not hit or tucheing the windows

but you have shown there lots of room to play wiht how much dooor did you cut

 

[tekdeus]

Most of the clearance I needed was done with a hammer But a small amount of cutting with tin snips was done as well. Not much trouble at all, maybe 15 minutes of work.

Got the deck, amps, and tweeters installed, and it sounds WAY better than the basic side-facing door speaker setup in my 84 Supra. Very good front stereo imaging with this system, all speakers are facing the driver's head.

Eclipse 7200 head with 100x2 A/D/S amp, A/D/S tweeters and crossovers:

 

[annoyingrob]

If you want to make "the best sound stage possible" I would highly recommend going active, and getting some time alignment as well.

The time alignment will make a world of difference.

 

[figgie]

dealing with speakers in the doors... you are looking at 3 feet to the drivers side speaker compared to nearly 6 feet to the passenger side speaker. No speakers (regardless of price) will fix the time coherent issue that you will face.

This needs some time delays built into the driver side speaker to match what is reaching your ear by the passenger side. If you are real creative you can use wave guides to help in time syncing but that will require dash removal

 

[Pernilongo]

dealing with speakers in the doors... you are looking at 3 feet to the drivers side speaker compared to nearly 6 feet to the passenger side speaker. No speakers (regardless of price) will fix the time coherent issue that you will face.

This needs some time delays built into the driver side speaker to match what is reaching your ear by the passenger side. If you are real creative you can use wave guides to help in time syncing but that will require dash removal

Yes the speaker won't fix time alignment. But there are head units for this purposes with "time alignment" function. Some have it pre-set some offer manual adjustment and there are some that offer both. There are head units that have a microphone that you attach to the headrest of the driver seat and then the head unit plays pink noise and determines sound alignment automatically. Very entertaining function in my opinion. You can actually feel the voice of the singer moving right to left when you adjust your alignment. I never heard of anything that can be build into the speaker to produce time delay, or maybe never came across something like this, VERY interesting though.

 

[tekdeus]

My Eclipse deck has time alignment, and I tried it out. It does make the music sound more centered, but somehow sounded more confined and mono to me. I put it back to no time alignment and it sounds wider and more spacious/stereo. Just my personal preference I suppose.

 

[figgie]

My Eclipse deck has time alignment, and I tried it out. It does make the music sound more centered, but somehow sounded more confined and mono to me. I put it back to no time alignment and it sounds wider and more spacious/stereo. Just my personal preference I suppose.

well on a properly setup system. The instruments can be located on the virtual stage within inches. Most instruments pass this. The ones that fail are usually the

Piano, Percussions and some string instruments like guitar or Cello.

Reason is because of the use of the lower end frequencies causes image shifting. I always used to ding cars during my judging days as they sounded quite well but failed every single time in those two areas as the piano, instead of being centered, Started on the right side of the dash and went to the left. The instruments do not move so niether should the imaging

You also have to remember, Time alignment of the fundamental wave is one thing. Then you have to deal with reflective waves which are usually the ones that kill a systems imaging as you have amplification of certain frequencies and cancellation of other frequencies. A car is a very reflective enclosure so that makes it very difficult if you do not have the correct time alignment from the get go (ie within an inch of one another). Also no amount of time correction will fix early and late reflections

 

[Pernilongo]

My Eclipse deck has time alignment, and I tried it out. It does make the music sound more centered, but somehow sounded more confined and mono to me. I put it back to no time alignment and it sounds wider and more spacious/stereo. Just my personal preference I suppose.

Eclipse is a pain in the ass to use in "sound-pro" mode. They offered time and db delay and didn't provide test CD with those units. Very strange to me. But i do know what you mean, electronic or synthetic music does sound better in "normal" mode.

 

[annoyingrob]

My Eclipse deck has time alignment, and I tried it out. It does make the music sound more centered, but somehow sounded more confined and mono to me. I put it back to no time alignment and it sounds wider and more spacious/stereo. Just my personal preference I suppose.

How many bands of adjustment does your EQ have?

What I do, is after I time align the speakers, start playing with the polarity of each driver. You'll likely find that swapping the polarity of one of your midranges will widen the soundstage significantly. After I've played with the polarity of all the speakers, I get some test tones centered on the frequencies of my EQ. First I start adjusting each frequency to a normalized volume level (I use an SPL meter for this). Then, I start adjusting the levels on each band left and right until it sounds centered. Of course, you need an EQ that allows separate left and right level adjustment.

The fact that the time alignment narrowed your soundstage points to some cancellations at certain frequencies. By removing your time alignment, you aren't really solving the problem, more masking it.

 

[Clip]

over my head, but this is pretty damn cool