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Mr. T

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I am running a simple 2 way active design for my front stage.

Mids: Seas Excel 6"
Mids will be mounted in sealed kick panels "on axis." I plan on tuning my front stage for both Driver seat, and Passengers seat. I imaged my Mids according to wear my ear drums are when I am sitting in the vehicle. I am using a laser and a mirror to do this. When Sitting in my driver seat The right mid will be imaged towards my driver's seat window. At that particular point the sound waves reflect off that window and into my left ear drum
Same thing for the passengers side except the sound waves coming from the left mid will travel across the cabin of the vehicle, bounce off a particular spot on the passenger side window and into the right ear drum of the passenger

My question is Diffraction. I understand how I am going to image my mids, but how to make my pod? I do not plan on using grills. My mids are 6" in diameter, is that how big I should make the diameter of my pod? Or should I have it extend out farther. If I do that will I have diffraction? Yes I will, so the only way to fix this is to round the corners?

My mids are 6" right. So make my pods 7." Flush Mount them. Now I have .5" Inches around the mid. I know I'd get diffraction, so could I just round that
.5" all the way around to rid of any diffraction?

What is the best way to do this?

Tweeter: I am very accustomed with fiberglass. I plan on fiberglassing up some A pillars. Tweeters will most likely be at shoulder level, about 2" or so up from my dash, correct? On axis or Off axis not sure yet.

Now reflection and diffraction are two different things correct? I know I am going to get reflection coming off the windshield and dash. As far as diffraction goes I have read some threads that stated you can use spheres, cut them in half and use them as "homes" for your tweet to be placed in. This will rid of diffraction. I have looked at several pics of this. I have noticed that in some tweeters, the half sphere is raised above the tweet several millimeters. (hope this makes sense) How far up should I go?

Also: I am able to do pretty much whatever I want with my A pillars. I have read that placing your tweeter 6" away from the dash and windshield and youll eliminate or reduce all reflections down to 470hz. If you take it that far, your tweeters will literally disappear.

Suggestions...........

Tweeter: Not sure yet, perhaps scans or the Peerless HDS tweeters

TokoSpeaker

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I wanna do the same with you, I use Seas Excel W16NX as midbass.
And I want to combine with RAAL 70-10D AM or HLCD Image Dynamics from Mr. Eric Stevens.

For RAAL, better to use with on axis on Pillar A and B at ear level high.
For HLCD, use it under dash.

I will try to compare with other midbass, such as Accuton Germany or Skaaning Denmark.
They are good quality products, too.

Thank you.

pjc

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I am gonna bump this for you because this is a similar setup that I am about to work on. You mentioned alot of things I wasnt thinking of. The kick aiming will be the same for me, and I am pretty set on doing my tweeters off axis. Curious to see any responses.

GlasSman

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Actually if I were you I would make the midrange kicks and some mounts for the tweeters based on what sounds best when aiming.....and from my experience most mids like to be vented as a sealed enclosure will give you peaky response in the upper midrange.

I always just cut a 3" hole in the back of the kick where it meets the carpet or where it meets the metal of the kick area depending on the vehicle and the design of the kicks.

Car audio speakers are designed to have good off axis response and you might find that after tweaking you get a better image with the speakers aimed even more off-axis than you expected or planned on.

GlasSman

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Actually......have you been to the Buwalda Hybrids forum? Scott would chime in and give his expert opinion if you get over there. That place is just as good as DIYMA and Scott is there more than he is here.

I always like to get as much info from the experts before I decide anything....of course just jumping in is a learning experience in itself.

subwoofery

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I am running a simple 2 way active design for my front stage.

Mids: Seas Excel 6"
Mids will be mounted in sealed kick panels "on axis." I plan on tuning my front stage for both Driver seat, and Passengers seat. I imaged my Mids according to wear my ear drums are when I am sitting in the vehicle. I am using a laser and a mirror to do this. When Sitting in my driver seat The right mid will be imaged towards my driver's seat window. At that particular point the sound waves reflect off that window and into my left ear drum
Same thing for the passengers side except the sound waves coming from the left mid will travel across the cabin of the vehicle, bounce off a particular spot on the passenger side window and into the right ear drum of the passenger

My question is Diffraction. I understand how I am going to image my mids, but how to make my pod? I do not plan on using grills. My mids are 6" in diameter, is that how big I should make the diameter of my pod? Or should I have it extend out farther. If I do that will I have diffraction? Yes I will, so the only way to fix this is to round the corners?
Don't bother with trying to create a round over for your mid. If you read the diffraction thread once more and calculate what size ball you need for your 6" to be able to play down to 80Hz-100Hz, you'll see why it's not worth it...

My mids are 6" right. So make my pods 7." Flush Mount them. Now I have .5" Inches around the mid. I know I'd get diffraction, so could I just round that
.5" all the way around to rid of any diffraction?

What is the best way to do this?

Tweeter: I am very accustomed with fiberglass. I plan on fiberglassing up some A pillars. Tweeters will most likely be at shoulder level, about 2" or so up from my dash, correct? On axis or Off axis not sure yet.

Now reflection and diffraction are two different things correct? I know I am going to get reflection coming off the windshield and dash. As far as diffraction goes I have read some threads that stated you can use spheres, cut them in half and use them as "homes" for your tweet to be placed in. This will rid of diffraction. I have looked at several pics of this. I have noticed that in some tweeters, the half sphere is raised above the tweet several millimeters. (hope this makes sense) How far up should I go?
Again, all the info to your question is in the diffraction thread (look up Patrick Bateman). It's well worth it for tweeters. It all depends how low you plan to cross your tweeter at. The sphere becomes larger the lower you cross... And you are correct, diffraction and reflection are 2 different things.

Also: I am able to do pretty much whatever I want with my A pillars. I have read that placing your tweeter 6" away from the dash and windshield and youll eliminate or reduce all reflections down to 470hz. If you take it that far, your tweeters will literally disappear.
Yup... Should help with reflections off the glass. The full wave would be 2.2kHz for 6" though... 470Hz is closer to 1/4 wavelength.

Suggestions...........

Tweeter: Not sure yet, perhaps scans or the Peerless HDS tweeters
Kelvin

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Everything down to the math is covered in here.

jooonnn

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i'd consider trying aiming the kicks at the dome light, as imo it would give an easier to work with image (in my experiences wider stage, more dynamic left and right contrast). I would do the opposite window aiming with the tweeters instead as it is a good compromise between helping a centered image and calming down reflections.

Thumper26

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For all speakers, it's which way sounds the best. Try your tweets every place you can. Test with and without the domes.

Same with mids. Aim for different things that can produce a symmetrical install. Dome light, headrest level (lay a board across the headrests and mark the midpoint), opposing headrests, windows, doors, whatever.

If you really want to get down to it, get your speakers measured with something like a dayton woofer tester, and then use the results to figure the best angle and enclosure size.

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