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iceteebone
07-25-2005, 08:43 PM
well i'm being talked into adding midbass but i really don't want to mod my car. i was thinking of making a center console with 2 8" mids. they would be up front underneath the dash but angled towards the seats. how do you guys think this will sound? does it sound like i'll have imaging problems? i'll have 4" mids in the doors, and tweets in the a-pillars. also i won't put mids in my doors because it's just not happening so please don't suggest that. :)

squeak9798
07-25-2005, 09:30 PM
Haha.....this was just discussed in length: http://forums.caraudio.com/vb/showthread.php?t=107962

Have fun :D

My personal opinion; what you want to do is far less than ideal, especially since you may need to cross the midbass as high as 300hz or so. In your situation, you'd definitely want the midbass in the doors (or atleast that location; outside edges of the vehicle, and front of the car as close towards the kicks as possible). With midbass aiming isn't as important (off-axis is fine), but location and pathlength differences are still important.

iceteebone
07-25-2005, 09:35 PM
Haha.....this was just discussed in length: http://forums.caraudio.com/vb/showthread.php?t=107962

Have fun :D

My personal opinion; what you want to do is far less than ideal, especially since you may need to cross the midbass as high as 300hz or so. In your situation, you'd definitely want the midbass in the doors (or atleast that location; outside edges of the vehicle, and front of the car as close towards the kicks as possible). With midbass aiming isn't as important (off-axis is fine), but location and pathlength differences are still important.


why would i need to cross them at 300 hz.? i would run the midbasses at say 70-80 hz. then the 4's and tweets at like 250-300 hz. and up and get a passive crossover for them.

squeak9798
07-25-2005, 09:39 PM
why would i need to cross them at 300 hz.? i would run the midbasses at say 70-80 hz. then the 4's and tweets at like 250-300 hz. and up and get a passive crossover for them.


Lowpass man. 300hz lowpass. You need to bandpass the midbass just like you do the midrange. So, you'd have a 70-80hz highpass, then a lowpass of ~300hz or so (depending on how low you play the midranges, over/underlap of xover points, etc). For, for our "estimation" purposes, lets go with 300hz as a "worst case" scenario :D So, the midbass would have a crossover point of around 300hz on the topend....which means they'd audibly be playing up to around 450hz or so (depending on slope....I just pulled that # out of the air and did no calculations to determine actual rolloff). And the higher in frequency range you go, the more localizeable the driver becomes if you don't position them accurately/accordingly. In this case, that means center of the vehicle would be a very poor location.

iceteebone
07-25-2005, 09:47 PM
how would it sound if i ran a single 8" midbass at say 70 hz. to 200 hz. in the center of the car? would that **** it up even more?

GCAdidas13
07-25-2005, 09:51 PM
Yes, sir.

squeak9798
07-25-2005, 09:52 PM
I guess the best response to that is read that thread and see which "side" you agree with. To sum up: You have audioholic and jlaine saying that midbass starts becoming localized and stereo around 80hz (hence, you would lose imaging and soundstaging), and then there is audiolife saying that it won't really hurt anything until you start getting up and over ~200hz-250hz.


Personally, as much as I like and respect Dave (audiolife).....I'm going to have to agree with audioholic and jlaine on this.

iceteebone
07-25-2005, 09:56 PM
I guess the best response to that is read that thread and see which "side" you agree with. To sum up: You have audioholic and jlaine saying that midbass starts becoming localized and stereo around 80hz (hence, you would lose imaging and soundstaging), and then there is audiolife saying that it won't really hurt anything until you start getting up and over ~200hz-250hz.


Personally, as much as I like and respect Dave (audiolife).....I'm going to have to agree with audioholic and jlaine on this.


i read the first 2 pages and saw 2 people arguing and throwing out words that sounded like jibberish to me. i think i'm just goona upgrade my stock speakers and call it a day

iceteebone
07-25-2005, 10:02 PM
the problem with my doors is the speakers are not mounted to the doorskin. they are mounted to the doorpanel. so should i cut the 4" hole big enough to fit a 6.5" mid and fiberglass around where the speaker mounts on the back side to stregthen it?

OlogyAudio
07-25-2005, 10:14 PM
AHHH -- I love these psychoacustic discussions... its all about the wavelength and pathlength diffrences (size of the cabin and location of source) -- and how the diffrent drivers sum at your head due to diffrent first path lengths (this isnt psychoacustics just time domain phase interactions...)... lets just say its a mess if you don't know exactly what you are doing :)

Edit:
You could just cut holes and reinforce.... Dayton RS drivers are awesome for the money...

iceteebone
07-25-2005, 10:29 PM
AHHH -- I love these psychoacustic discussions... its all about the wavelength and pathlength diffrences (size of the cabin and location of source) -- and how the diffrent drivers sum at your head due to diffrent first path lengths (this isnt psychoacustics just time domain phase interactions...)... lets just say its a mess if you don't know exactly what you are doing :)

Edit:
You could just cut holes and reinforce.... Dayton RS drivers are awesome for the money...


i really hate making holes in my door panels. what would you use to make like a 4" hole bigger? also i was thinking of some vifa 7" mids. could i bandpass those vifas at 80-2khz? and then the tweeters play above that?

iceteebone
07-25-2005, 10:58 PM
actually now i think my car has 5 1/4" speakers. according to crutchfield it does, so i guess i'll go with 5.25 mids. the opening though is only like 3.5" big. anywho here is a pic of a door that looks like mine. it isn't mine though.

http://img143.imageshack.us/img143/468/62832519full4dm.jpg

iceteebone
07-25-2005, 11:24 PM
upon further review i have 5 1/4" speakers not 4's so i'll just get some 5.25 mids and a set of tweeters and run it active and call it a day.

req
07-25-2005, 11:59 PM
you would always get some 1\2~1" MDF and make new baffles. looks like theres TONS of room under that doorpanel to make more depth. so do somthing like this;

http://img340.imageshack.us/img340/1053/baffle6ub.gif

just cut a ring for them 6.5's or 7's and mount it over the existing hole for the door. if the magnet\basket is too large to fit in the old hole, cut it a little bigger to fit. if the depth for the window is too shallow, add another .5" piece of MDF there.

all you gotta do is extend outward (hence the 3\4" mdf baffle) and maybe make the hole a little larger :)

the hump in the door panel you got looks to be a good 3" deep between the metal and the actual vynl\grill part where the 5.25's are mounted. i think you should be able to fit some large speakers in there. but you better deaden that door properly :)

iceteebone
07-26-2005, 12:10 AM
so what you are saying is i should make a 3/4" mdf ring and mount the ring on the outside of the door panel and then mount the speaker, and with the baffle the magnet should fit in through the existing hole? should i also fiberglass the door panel from behind for extra strength?

OlogyAudio
07-26-2005, 01:12 AM
so what you are saying is i should make a 3/4" mdf ring and mount the ring on the outside of the door panel and then mount the speaker, and with the baffle the magnet should fit in through the existing hole? should i also fiberglass the door panel from behind for extra strength?

Were saying you have some cutting to do... also your door can never be strong enough ;) do all that you can in terms of bracing and damping. Fiberglassing behind is a great idea... If you can use MDF for bracing as well great (cheaper too)!

iceteebone
07-26-2005, 01:17 AM
Were saying you have some cutting to do... also your door can never be strong enough ;) do all that you can in terms of bracing and damping. Fiberglassing behind is a great idea... If you can use MDF for bracing as well great (cheaper too)!


but if i mount the mid and mdf ring on the outside of the panel, where you can see it inside the car, i wouldn't have to make the hole that much bigger right? plus i have all the supplies to fiberglass. then should i deaden the hole door panel and seal off the outer doorskin?

OlogyAudio
07-26-2005, 01:21 AM
but if i mount the mid and mdf ring on the outside of the panel, where you can see it inside the car, i wouldn't have to make the hole that much bigger right? plus i have all the supplies to fiberglass. then should i deaden the hole door panel and seal off the outer doorskin?

well you would still need to make a hole -- http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=295-364&DID=7 is the ideal driver unless you don't like a detialed sound -- in which case a vifa with a poly cone at about $50-60 wouldn't cost that much more and still sound good... :)

If you run into troubles with mounting depth you can gain a little over an inch by removing the shielding cup and bucking magnet... I already have a very nice design with that driver and the dayton RS tweeter :)

iceteebone
07-26-2005, 01:28 AM
well you would still need to make a hole -- http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=295-364&DID=7 is the ideal driver unless you don't like a detialed sound -- in which case a vifa with a poly cone at about $50-60 wouldn't cost that much more and still sound good... :)

If you run into troubles with mounting depth you can gain a little over an inch by removing the shielding cup and bucking magnet... I already have a very nice design with that driver and the dayton RS tweeter :)


well i have a set of boston acoustic pro 6.5's i think i'll mount in my doors now. the mounting diameter is 5" and the opening in my door is 4.25" so i won't have to cut too much.

OlogyAudio
07-26-2005, 01:33 AM
well i have a set of boston acoustic pro 6.5's i think i'll mount in my doors now. the mounting diameter is 5" and the opening in my door is 4.25" so i won't have to cut too much.

that works :) those BAs are nice -- not in the same league as the dayton drivers :) but still great nontheless

fossil99ca
07-26-2005, 08:22 AM
so what you are saying is i should make a 3/4" mdf ring and mount the ring on the outside of the door panel and then mount the speaker, and with the baffle the magnet should fit in through the existing hole? should i also fiberglass the door panel from behind for extra strength?


I don’t know if have taken your door panels off yet. But just the cosmetic grill might be mounted to the door skin. Take your door panel off. I wouldn’t be surprised if the speaker is actually mounted to the steel part of the door.

If I were you, I would look into mounting the speaker to the metal part of your door, not the plastic. Make those MDF baffles to space the speaker off the metal part of the door so they just clear the underside of the plastic grill. You won’t need to reinforce the plastic; maybe just some sound deadening is you want.

If you want to keep the stock look, you could even oversize the speaker larger than the grill and have it overlap the grill slightly (go 6-1/2”). It’s not ideal (since your blocking part of the speaker) but again you keep the stock look.

iceteebone
07-26-2005, 10:56 AM
I don’t know if have taken your door panels off yet. But just the cosmetic grill might be mounted to the door skin. Take your door panel off. I wouldn’t be surprised if the speaker is actually mounted to the steel part of the door.

If I were you, I would look into mounting the speaker to the metal part of your door, not the plastic. Make those MDF baffles to space the speaker off the metal part of the door so they just clear the underside of the plastic grill. You won’t need to reinforce the plastic; maybe just some sound deadening is you want.

If you want to keep the stock look, you could even oversize the speaker larger than the grill and have it overlap the grill slightly (go 6-1/2”). It’s not ideal (since your blocking part of the speaker) but again you keep the stock look.


the speaker is attached to the plastic panel and not the metal doorskin.

GCAdidas13
07-26-2005, 11:04 AM
pull a gcadidas and do what is linked in my signature under koda pods. :D

iceteebone
07-26-2005, 11:09 AM
pull a gcadidas and do what is linked in my signature under koda pods. :D


you could not even imagine the mess i would have if i tried to make fiberglass pods like that. the magnet on my BA's fits through that hole in my door it's just the basket i'm worried about. i'll just extend outwards till it fits. might do i little fiberglassing, but not much.