looking to add midbass

[iceteebone 5,000+ posts]

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. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Click to read more...

 

[squeak9798 5,000+ posts]

Haha.....this was just discussed in length: http://forums.caraudio.com/vb/showthread.php?t=107962

Have fun //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

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 5,000+ posts]

Haha.....this was just discussed in length: http://forums.caraudio.com/vb/showthread.php?t=107962
Have fun //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

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 5,000+ posts]

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 //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif 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 5,000+ posts]

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 10+ year member]

Yes, sir.

 

[squeak9798 5,000+ posts]

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 5,000+ posts]

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 5,000+ posts]

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 10+ year member]

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 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Edit:

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

 

[iceteebone 5,000+ posts]

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 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
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 5,000+ posts]

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.

 

[iceteebone 5,000+ posts]

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 5,000+ posts]

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;

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 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

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 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[iceteebone 5,000+ posts]

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?