# Underseat midbass



## ECM (Dec 23, 2007)

Seeing those BMW's with 8" speakers under the seat left me wondering if it would be feasible to install horns under the dash and midbass under the seats. Would they be able to play up to 700Hz or 800Hz and still sound good?

As we know, in the past folks have installed midbass in the rear quarter panels with good results so that leads me to believe it's not necessary to have them in the kick panels or doors. But under the seats? I'm not so sure.

Opinions?


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## HertzGuy (Jan 23, 2010)

I remember back in the day, a company was making those bass shakers, and you mounted them under the seat.
I always wanted to hear someone with those in their car, but I didn't know anyone silly enough to buy them!


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## quality_sound (Dec 25, 2005)

This is something else entirely. Not a bass shaker but and actual midbass/small sub. 

ECM it won't work for what you want to do I don't think. I have tried a crappy midbass location up to 300Hz that worked fine but at 700-800Hz you're in the midrange area and that will pull the sound under the seat. 

I know there's a few guys here that have replaced the dirvers under their seats and I'll be doing it here before too long.


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## audiguy (Jul 30, 2007)

The 8" in the BMW are crossed at 160hz. 800 is an entirely different story. 

There are a lot of things to like about 8's under the seats. One is an isolation of the sound from the foot and door area.


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## lycan (Dec 20, 2009)

quality_sound said:


> This is something else entirely. Not a bass shaker but and actual midbass/small sub.
> 
> ECM it won't work for what you want to do I don't think. I have tried a crappy midbass location up to 300Hz that worked fine but at 700-800Hz you're in the midrange area and that will pull the sound under the seat.
> 
> I know there's a few guys here that have replaced the dirvers under their seats and I'll be doing it here before too long.


This much makes sense to me :

Below ~300Hz, certainly, it's all about ITD and the corresponding cone-of-confusion. A location below your seat happens to be a rather "shallow" cone ... essentially indistinguishable to a location right in front of you, over your head, or directly behind you. But under-seat might even be "better", in terms of less sensitivity to head-turning 

Can be electronically moved to a "steeper" cone, methinx  Check the midbass array discussions ...


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## HertzGuy (Jan 23, 2010)

I know that wasn't what he was talking about, it just made me think of those bass shakers LOL, thats all.


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## beerdrnkr (Apr 18, 2007)

I had ideas about adding the dayton RS 8's under my seats along with the set I have in my doors for a good amount of midbass. I know it'd take a lot of processing to match T/A. I've been too chicken to try it out.


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## HertzGuy (Jan 23, 2010)

Just out of curiosity what type of cars are we talking about here. I look under my seats and theres barely room for a smallish 4ch amp, and you guys are talking of mounting an 8in mid bass woofer...how is this done?


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## ECM (Dec 23, 2007)

HertzGuy, some BMW's have 8" speaker enclosures under the front seats.

quality_sound, your point makes sense to me. Be better to have them as dedicated midbass and maybe some midrange in the kicks or doors. That would at least help with door rattles since they won't be playing too low.


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## dvsadvocate (Mar 17, 2008)

Steve Head aka Audionutz mounted a 10inch Oz Audio driver underneath the seat of his Civic. It was freeair and he cut a hole underneath to let the driver go through.


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## tgnylu (Aug 28, 2009)

HertzGuy said:


> I know that wasn't what he was talking about, it just made me think of those bass shakers LOL, thats all.


Even though they're on sale at Madisound, I bet they still haven't sold any! Aurasound AST-2B-4 Pro Bass Shaker each from Madisound


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## quality_sound (Dec 25, 2005)

ECM said:


> HertzGuy, some BMW's have 8" speaker enclosures under the front seats.
> 
> quality_sound, your point makes sense to me. Be better to have them as dedicated midbass and maybe some midrange in the kicks or doors. That would at least help with door rattles since they won't be playing too low.


All of the 06+ 3-series and 5-series have them under the seat and I believe the new 5- and 7-series will have them as well. The only PITA is the limited mounting depth.


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## s4turn (Jun 17, 2009)

interesting...

so under seat midbass is fine up to 300hz? 

I thought after 100hz? sound become quite directional?


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## traceywatts (Jun 2, 2008)

s4turn said:


> interesting...
> 
> so under seat midbass is fine up to 300hz?
> 
> I thought after 100hz? sound become quite directional?


in that range, directionality is more l to r than up and down. since these are playing thru the center or your head, there is no l to r difference.


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## tornaido_3927 (Nov 23, 2009)

I really want to do this underseat midbass, I love the idea of it..

But what would be some effective ways of mounting, say with a shallow driver under the seat, preferably avoiding cutting through the chassis?

Does having the driver under the seat not muffle the sound at all, or does it work similar to how a sub plays from the boot but still works?


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## quality_sound (Dec 25, 2005)

If you don't want to cut anything then your best bet is to find a shallow mount woofer and build an enclosure for it. I'm going to do something similar in my wife's Wrangler. 

I doesn't muffle it at all, at least not in my car.


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## tornaido_3927 (Nov 23, 2009)

Yeah I have some shallow woofers on the way, as I don't have alot of room..

But I was wondering on specifics, I know speaker TS parameters will affect this but I'm wondering in general terms for an underseat midbass enclosure, would you go sealed or ported? If ported, which way would you fire the port? Or would you horn load it into the footwell? Etc..

Sorry if these are total noob questions.. I just haven't been able to find much specific info on this..


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## quality_sound (Dec 25, 2005)

I'd go sealed simply because it's going to be a much smaller enclosure.


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## tornaido_3927 (Nov 23, 2009)

That's a good point, I'm glad I asked.. And thanks for the reply


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## Slammed Rod (Jan 23, 2010)

Glad this topic came up!! I wanted to ask about midbass under the seat ,but figured I'd get a bunch of ribbing about it!!! Glad it works!!!.I have a set of RE XXX mids I'm going to pop in under me seats.I have enough room under there for 2 6packs plus!!!!Anyone know what size the RE XXX 6.5 sealed box should be???


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## T3mpest (Dec 25, 2005)

Slammed Rod said:


> Glad this topic came up!! I wanted to ask about midbass under the seat ,but figured I'd get a bunch of ribbing about it!!! Glad it works!!!.I have a set of RE XXX mids I'm going to pop in under me seats.I have enough room under there for 2 6packs plus!!!!Anyone know what size the RE XXX 6.5 sealed box should be???



Post up t/s, but as a 6.5 I can't imagine it's very big. .5 cube?


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## s4turn (Jun 17, 2009)

the only thing with a XXX mid is the depth though 

I know I can only fit 100mm max under my set.. so once the encosure is in.. not much space at all for a decent midbass (for me)


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## Slammed Rod (Jan 23, 2010)

I have at least 6" of space height wise under my seat,so it shouldn't be a problem.I'm trying to find some specs on the XXX.Nothing on thier site seeing they sell them as comps now.I bought these back in '05 and they've been in my closet in the box since.Never put them in,but going to use them now!I looked at Ultra's site and the 6.5 requires a .4cubed sealed.So I shouyld be fine with something between that and .5.


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## norcalsfinest (Aug 30, 2008)

if i ever went 3 way, i'd love to do this in the xB. tweets in the sails, 5.25's in the kicks, and 8's crossed really low under the front seats. hell, i could fit 10's if i wanted


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## thehatedguy (May 4, 2007)

Yeah but Steve's 10s are subwoofers. His midbasses are in the kicks.



dvsadvocate said:


> Steve Head aka Audionutz mounted a 10inch Oz Audio driver underneath the seat of his Civic. It was freeair and he cut a hole underneath to let the driver go through.


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## s4turn (Jun 17, 2009)

if they are the older XXX mids (chrome magnet, no XXX logo)
T/S parameters are:
Specs for the XXX 6.5:
RE: 1.75 Ohms
Fs: 47.4 Hz
Qms: 2.33
Qes: 0.59
Qts: 0.473
Mms: 15.04 g
Cms: 7.505E-04
Vas: 21.49 ltr
1- way Xmax: 13mm linear (verified via Klippel)
Le: 0.14mH
Bl: 3.636 t/m
Power: 150wrms
Spl: 87.75 dB 1W/1m

not sure about the newer XXX mids

old ones here:

















these were taken from nzice - pauls audio
which I have just brought myself


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## dodgeman70592 (Jun 16, 2009)

dvsadvocate said:


> Steve Head aka Audionutz mounted a 10inch Oz Audio driver underneath the seat of his Civic. It was freeair and he cut a hole underneath to let the driver go through.


I wonder how they hold up in inclimate weather?


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## drumcrusher (May 4, 2008)

Ive considered building enclosures for my midbass in front of my front seats pointing toward the kick panel/ dash area because of the bad stock speaker locations, and lack of depth in my doors. there is no room under my front seats at all. sounds like something i would have done back in high school, but hey, if it works... right?

has anyone tried this???

may open up more options as far as speaker choices too.


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## s4turn (Jun 17, 2009)

or a deep puddle


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## quality_sound (Dec 25, 2005)

drumcrusher said:


> Ive considered building enclosures for my midbass in front of my front seats pointing toward the kick panel/ dash area because of the bad stock speaker locations, and lack of depth in my doors. there is no room under my front seats at all. sounds like something i would have done back in high school, but hey, if it works... right?
> 
> has anyone tried this???
> 
> may open up more options as far as speaker choices too.


It's been tried and works fine.


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## tornaido_3927 (Nov 23, 2009)

drumcrusher said:


> Ive considered building enclosures for my midbass in front of my front seats pointing toward the kick panel/ dash area because of the bad stock speaker locations, and lack of depth in my doors. there is no room under my front seats at all. sounds like something i would have done back in high school, but hey, if it works... right?
> 
> has anyone tried this???
> 
> may open up more options as far as speaker choices too.


I don't know if you've seen this thread but it has a couple of guys who have done a similar thing to what you're looking at.. Seems as though they love it!


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## drumcrusher (May 4, 2008)

thanks for the help guys. im halfway done with some "spherical" pods for mids and tweets in the dash. i have hertz hks or peerless sls 6.5's at my disposal at the moment. im leaning toward the sls's under the seats crossed as low as my mids will allow. 

the hertz 6.5's, at the moment, are mounted in the stock sealed enclosure in my door. they sound good except for the bad location in the back of the door. does anyone think they can compair to the sls's for midbass? im thinking +/- 250hz and down...
thanks for your help in advance...


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## chithead (Mar 19, 2008)

If all goes well, I will be putting 10" midbass under my front seats soon. I'll keep you updated and let you know how it goes.


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## ECM (Dec 23, 2007)

Thinking of getting a BMW in the next year or two, depending on when I move back to the states. I've picked up a pair of BNIB illusion audio ND-8's...perfect for the job.

But it appears I'll need some mids in the kicks as well. Did illusion make 5.25" flat mids?


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## Slammed Rod (Jan 23, 2010)

s4turn said:


> if they are the older XXX mids (chrome magnet, no XXX logo)
> T/S parameters are:
> Specs for the XXX 6.5:
> RE: 1.75 Ohms
> ...


Those are the ones I have!!! Thanks!!!


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## quality_sound (Dec 25, 2005)

ECM said:


> Thinking of getting a BMW in the next year or two, depending on when I move back to the states. I've picked up a pair of BNIB illusion audio ND-8's...perfect for the job.
> 
> But it appears I'll need some mids in the kicks as well. Did illusion make 5.25" flat mids?


They'd have to be fabbed in there since the mids are now door mounted. But yes, Illusion did have 5.25"s.


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## ECM (Dec 23, 2007)

quality_sound said:


> They'd have to be fabbed in there since the mids are now door mounted. But yes, Illusion did have 5.25"s.


Ah, always a catch huh? I did notice the door panels now have speaker grills, but they are pretty far up, not good for pathlength difference. 

Either way, I'll keep an eye out for 5.25's. It will be a while before I move back anyway...

BTW, AMMO sucks!

ECM


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## mosca (Oct 26, 2009)

I don't know the depth for the ND-8's, but the depth available underseat is limited to not much more the 70mm because part of the speaker goes under the seat rail (at least on 1 and 3 series).


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## mosca (Oct 26, 2009)

ECM said:


> Ah, always a catch huh? I did notice the door panels now have speaker grills, but they are pretty far up, not good for pathlength difference.
> 
> Either way, I'll keep an eye out for 5.25's. It will be a while before I move back anyway...


yes, it is quite far up. I don't know which model you're getting, but you can't really put anything bigger than 4 inchers on the stock position on some series.


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## mosca (Oct 26, 2009)

here's a video of an Earthquake SWS-8 in a BMW E92 M3 at work:


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## WAwatchnut (Sep 5, 2009)

HertzGuy said:


> I remember back in the day, a company was making those bass shakers, and you mounted them under the seat.
> I always wanted to hear someone with those in their car, but I didn't know anyone silly enough to buy them!


I always wondered about the bass shakers. They're still being sold by a couple of companies. They're somewhat popular for home theater... I've wanted to try out a set for that use. Seems like a cheap toy to have fun with for a while.

And now there's the Rockford Fosgate IBeam...

IBeam® is the next generation of high definition bass solutions. It efficiently energizes the listeners auditory cortex without pressurizing surrounding air by transmitting information via bone harmonics and other direct stimulus routes. IBeam® localizes bass and reduces "noise pollution" by increasing the portion of tactile sound as "felt" by only the listener. ​


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## HIS4 (Oct 6, 2005)

If anybody is curious, here's more pics of the underseat enclosures in the newer BMWs.

Stock enclosure with Earthquake SWS-8 installed:
That binding post terminal is not OEM.


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## nismos14 (Jun 22, 2007)

Or you could be like me........ 8's in all 4 doors 10's in rear deck... lol kidding (But I really do have all that ). Good/interesting topic.


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## nismos14 (Jun 22, 2007)

HIS4 said:


> If anybody is curious, here's more pics of the underseat enclosures in the newer BMWs.
> 
> Stock enclosure with Earthquake SWS-8 installed:
> That binding post terminal is not OEM.
> ...


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## putergod (Apr 23, 2008)

Am I the only one that find this utterly retarded?



dvsadvocate said:


> Steve Head aka Audionutz mounted a 10inch Oz Audio driver underneath the seat of his Civic. It was freeair and he cut a hole underneath to let the driver go through.


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## bassfromspace (Jun 28, 2016)

putergod said:


> Am I the only one that find this utterly retarded?


I'm sure.


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## boltupright (Feb 14, 2007)

for midbass, it's best to hear the right midbass with the right ear and the left midbass with the left ear so you get that nice separation for emotional impact. If you need to put the midbass under the seats make sure they are to the right and left as far as possible and maybe put some kind of sound barrier under the seats so less of the right midbass is heard with the left ear, and vice versa.


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## putergod (Apr 23, 2008)

bassfromspace said:


> I'm sure.


Then I guess I'm alone in wanting to maintain structural integrity to my car, and my costly components!


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## 6spdcoupe (Jan 12, 2006)

HIS4 said:


> If anybody is curious, here's more pics of the underseat enclosures in the newer BMWs.
> 
> Stock enclosure with Earthquake SWS-8 installed:
> That binding post terminal is not OEM.


Dyn 162/162GT/Esotar 650/172 will all also work as well...


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## Q-Authority (Mar 31, 2008)

WAwatchnut said:


> I always wondered about the bass shakers. They're still being sold by a couple of companies. They're somewhat popular for home theater... I've wanted to try out a set for that use. Seems like a cheap toy to have fun with for a while.


I finally got to listen to a setup using them, in a MKI MR2 a few months or so back, and was somewhat impressed with the sound. The owner had gottena a set dirt cheap, and just threw one of them into the car for the heck of it. Sure, you're not going to mistake it for a really good sub, but none the less it was much better than I had guessed they might be, and certainly better than a lot of so called decent sub setups I have heard. It wasn't even set up in the best manner yet, as, if I recall properly, the owner hadn't actually completely screwed/bolted it down to the floor pan yet. I would like to hear it again if they do get around to attaching it completely.


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## Mic10is (Aug 20, 2007)

putergod said:


> Then I guess I'm alone in wanting to maintain structural integrity to my car, and my costly components!


Car is trailered and he lives in FLA

thats also one of the best sounding cars ever built so....yeh you are pretty much alone on this one


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## HIS4 (Oct 6, 2005)

nismos14 said:


> How do the earthquakes sound in there? Is that your car? External Amp?


Pretty decent for what it is. It doesn't go ultra low but its usable down to 30 hz. I'm powering them off channels 5/6 of a Zapco DC650.6. Its important to use them with a mid that can go pretty low though as they don't sound very good above 120Hz.


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## 6spdcoupe (Jan 12, 2006)

putergod said:


> Am I the only one that find this utterly retarded?


I would have to go with ...


... Yes !


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## quality_sound (Dec 25, 2005)

The sheetmetal in the floor plays almost nopart in the car's structural integrity. Also, it not like he cut a hole and left it empty. I'll bet it's stronger now than before. Last, I'm pretty sure the car is a trailer queen.


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## bassfromspace (Jun 28, 2016)

HIS4 said:


> Pretty decent for what it is. It doesn't go ultra low but its usable down to 30 hz. I'm powering them off channels 5/6 of a Zapco DC650.6. Its important to use them with a mid that can go pretty low though as they don't sound very good above 120Hz.


1 or 2?


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## putergod (Apr 23, 2008)

Ummm.. wow... All I can say.

I guess we can agree to disagree...


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## Q-Authority (Mar 31, 2008)

6spdcoupe said:


> I would have to go with ...
> 
> 
> ... Yes !


Well personally I would vote for it looking pretty goofy as well, buy hey, whatever floats their boat. A person can do whatever they want with their own property.

As for it being one of the best sounding cars ever, I would have to hear it to believe it. I have a hard time believing a woofer firing off of a hard pan, just a few inches below it doesn't have some sort of detrimental effect, even with the opening to the rear.


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## 6spdcoupe (Jan 12, 2006)

Q-Authority said:


> Well personally I would vote for it looking pretty goofy as well, buy hey, whatever floats their boat. A person can do whatever they want with their own property.
> 
> As for it being one of the best sounding cars ever, I would have to hear it to believe it. I have a hard time believing a woofer firing off of a hard pan, just a few inches below it doesn't have some sort of detrimental effect, even with the opening to the rear.


So then by theory, you listen with your eyes ? 

Steve, the owner of the vehicle, has an idea or two about what he is doing and what works well. I have dabbled a bit as well and I would have zero doubts that he made this work very well despite some peoples thoughts on it's "goofy" -ness.


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## SpecV (Mar 26, 2009)

i have a aset of the kicker ssmb8 that i might try this with.


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## Q-Authority (Mar 31, 2008)

6spdcoupe said:


> So then by theory, you listen with your eyes ?
> 
> Steve, the owner of the vehicle, has an idea or two about what he is doing and what works well. I have dabbled a bit as well and I would have zero doubts that he made this work very well despite some peoples thoughts on it's "goofy" -ness.


That's it, pull something completely out of thin air, and use it to try and debase a perfectly honest critical assessment.

Of course, I don't see sound, I taste it, like any other normal person. Haven't you have ever heard of synaesthesia.:laugh:

I just don't recall ever having heard a sub (not including bass-reflex), without any baffling material, sounding quite right with a parallel back board that close to it.


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## thehatedguy (May 4, 2007)

Steve's last version of the Civic in the pictures is on of the best cars that I have ever heard. The Oz subs under the seats are designed of IB use and that is how they are being used.


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## magee2122 (Jun 26, 2009)

Im doing a set of JL audioZR800-CW in two weeks in my titan. Cant wait to see what they do.


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## quality_sound (Dec 25, 2005)

ECM said:


> Ah, always a catch huh? I did notice the door panels now have speaker grills, but they are pretty far up, not good for pathlength difference.
> 
> Either way, I'll keep an eye out for 5.25's. It will be a while before I move back anyway...


I guess it depends on if you're going for a 1 or 2 seat car. if 1 seat you can align them electronically. Plus the clarity will be a bit better being up top. I do know some shallow 5.25s will fit in that location as well. I've seen some of the newer Quarts in that location. 



> BTW, AMMO sucks!
> 
> ECM


Tits, clits, and beer cans!


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## lycan (Dec 20, 2009)

boltupright said:


> for midbass, it's best to hear the right midbass with the right ear and the left midbass with the left ear so you get that nice separation for emotional impact. If you need to put the midbass under the seats make sure they are to the right and left as far as possible and maybe put some kind of sound barrier under the seats so less of the right midbass is heard with the left ear, and vice versa.


completely wrong.

Fortunately, too, since what you suggest would be next to impossible to achieve at midbass wavelengths.

We localize midbass by hearing EACH driver with BOTH ears. In fact, classic stereo _requires_ it ... you can't have an ITD, unless the source can be heard by _both_ ears.

I do agree, though, that we should try to get the drivers as far to the left & right as possible, for best ITD and resultant stage width. However, if you can find a better location at less-than-optimal width (perhaps a better enclosure, for example), there are electronic techniques that can help restore width.


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## HIS4 (Oct 6, 2005)

bassfromspace said:


> 1 or 2?


One under each front seat.


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## orangelss (Dec 20, 2008)

Just a observation. With the panel that close to the back of the driver. I would think it would help load the back wave a bit and help control the cone excursion. The opening is still plenty large to allow the speaker to operate free-air.


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## ECM (Dec 23, 2007)

orangelss said:


> Just a observation. With the panel that close to the back of the driver. I would think it would help load the back wave a bit and help control the cone excursion. The opening is still plenty large to allow the speaker to operate free-air.


Good call. I've seen subs in convertible cars loaded that way as well so they don't just flap around. In the convertible I saw, a baffle was installed in front of the cone, around two or three inches away. Same concept though.


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## danielp (Jan 6, 2010)

Also consider the Earthquake SwS range of shallow subs.
They come in 6.5 and 8'.

I am going to put 2 under each of the front seats in its own enclosures.
Will let you guys know how it turns out.


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## ar3nbe (Oct 1, 2007)

Apart from the Earthquakes, what other shallow mount options are available in a 6.5, maybe 8inch ? Frequency range of 80-300 or so needed. 

Under 70mm is preferred.


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## the_orb (Oct 20, 2009)

what about Rockford's new Tactile Transducer?
I heard it's as great as it claimed to be...


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## t3sn4f2 (Jan 3, 2007)

ECM said:


> Good call. I've seen subs in convertible cars loaded that way as well so they don't just flap around. In the convertible I saw, a baffle was installed in front of the cone, around two or three inches away. Same concept though.


I don't see how such a large opening so close to the cone could ever affect the IB enclosure. I don't think he would have ever designed it that way if it did either.


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## de hero (Jun 20, 2008)

Could the Tympany LAT 250 be an option here :-









Tymphany LAT 250 Specifications: 
*Power handling: 100 watts RMS/200 watts max 
*Le: 0.27 mH 
*Impedance: 2 ohms 
*Re: 2 ohms 
*Frequency response: 60-1,600 Hz 
*Fs: 60 Hz 
*SPL: 84.5 dB 1W/1m 
*Vas: 0.31 cu. ft. 
*Qms: 3.4 
*Qes: 1.0 *Qts: 0.79 
*Xmax: 3 mm 
*Dimensions:
A: 10.2" x 3.5",
B: 9.4" x 2.7",
C: 1.35" (half of total diameter). 


From what I recall having done a little research a good while back - they require an inconveniently large (for under the seat) enclosure, and I dont think they go very low. But for the price could be worth an experiment perhaps?


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## HIS4 (Oct 6, 2005)

ar3nbe said:


> Apart from the Earthquakes, what other shallow mount options are available in a 6.5, maybe 8inch ? Frequency range of 80-300 or so needed.
> 
> Under 70mm is preferred.


The SWS is not a good choice for that passband. They are designed to work as subwoofers so they don't do well playing higher up into the midrange passband. My SWS-8 doesn't sound good above 120Hz. You'd probably want to look into Morels, Dynaudio or maybe even the Hertz Space 8 for that passband.


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## JLawsonz (Jun 4, 2009)

On the subject of under seat midbass. This reminds me of what I did way back in the day (early 90's) in trucks to smooth out the bottom end when space was lacking. I always played from 60-100 Hz up to 150 to 300 Hz depending on the size of the sub. I used 6.5", 8" or 10" depending on what enclosure fit well. Phasing and time aligning does get tricky

It gave a nice kick from the front and gave a little more feel through the seat instead of on your leg from the kickpanel or door.

On the subject of those bass shaker devices, they are not made for sound, but to give the "feel" that you are playing your system loud enough to shake the car. It DOES enhance the experience, but does nothing for SQ.

The key is to have an enclosure large enough to suit the driver. I've heard Pioneer Premier 6" midbass drivers under the front seats of a Mercedes with the right enclosure and power which sounded amazing.

I'm no expert, just giving $.02 worth.


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## t3sn4f2 (Jan 3, 2007)

de hero said:


> Could the Tympany LAT 250 be an option here :-
> 
> View attachment 16087
> 
> ...


Zaph|Audio

"Tymphany LAT-250 test results...

[Image] - LAT-250 Frequency response 
[Image] - LAT-250 Harmonic distortion 
[Image] - LAT-250 Impedance close-up 
[Image] - LAT-250 3 tone IMD @ 50Hz 
[Image] - LAT-250 3 tone IMD @ 60Hz 
[Image] - LAT-250 3 tone IMD @ 90Hz 
[Image] - LAT-250 3 tone IMD @ 150Hz 

Results are in and they are kinda strange. Not surprising, since the driver itself is kinda strange. Fs was kinda high, and not very pronounced, and this was after a substantial break-in and cool down period. It's way higher than the spec sheet says. This "subwoofer" doesn't have much low end extension at all. Note that I could not get accurate T/S numbers on this driver. With an almost non-existant Fs impedance peak, I could not get a good delta compliance Vas number. There's no way to do a delta mass on this driver either. Anyone trying to use this driver will likely need to just put it in some experimental boxes and see what works. 

With the lack of low end extension, I don't really see any effective use of this driver without active response shaping. Distortion is good above 90 Hz and excellent at 150 Hz, but slightly high lower in frequency where cleanliness is really needed. The bottom line is that this system has seriously limited usefulness - it's your only option if you absolutely must have a woofer that is 3" wide. This is essentially ten 2-1/2" woofers, but performance wise, it will be drastically outperformed in almost every way by just about any 8" woofer. 

The test results of this small version may not represent the usefulness and effectiveness of the larger versions, but I do have my expectations. I think the real problem with the LAT woofers is that they still have traditional Thiele/Small parameters. A certain volume displacement is going to require a certain cabinet volume. That renders any slim profile almost useless if it has to go in a big box anyway. The LAT has some interesting engineering and features but Hoffman's Iron Law remains in full effect. "


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## diamondjoequimby (Jun 30, 2009)

thehatedguy said:


> Steve's last version of the Civic in the pictures is on of the best cars that I have ever heard. The Oz subs under the seats are designed of IB use and that is how they are being used.



I am sure it sounds great, but imo that is not a car if it can't reasonably be driven. If you want something to pull around on a trailer that can't be driven just mock up a listening room and slap casters on it.


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## Q-Authority (Mar 31, 2008)

diamondjoequimby said:


> I am sure it sounds great, but imo that is not a car if it can't reasonably be driven. If you want something to pull around on a trailer that can't be driven just mock up a listening room and slap casters on it.


That's my exact feeling!


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## quality_sound (Dec 25, 2005)

Why couldn't it be driven? I've owned cars that were a lot lower than Steve's Civic. A hell of a lot lower. The ONLY time he's have a problem would be if he parked in an 18" deep puddle.


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## 4l0 4ever (Dec 25, 2009)

I have fitted a 12" Phase Linear Aliante Limited sub in a .4 cubic foot box in the passenger footwell, with half going behind the dash in a MG Metro. Have also seen wedges in front of the front seats with compound pairs of 6.5" speakers in 4th order band pass arrangements.

Anything is possible....


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## pyropoptrt (Jun 11, 2006)

diamondjoequimby said:


> I am sure it sounds great, but imo that is not a car if it can't reasonably be driven. If you want something to pull around on a trailer that can't be driven just mock up a listening room and slap casters on it.


Steve's civic was trailered to shows but was also used as his daily driver with a 2 hour commute (one-way) every day.


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## diamondjoequimby (Jun 30, 2009)

pyropoptrt said:


> Steve's civic was trailered to shows but was also used as his daily driver with a 2 hour commute (one-way) every day.


with the subs exposed like that? Sorry, that is just flat not practical. There is so much debris and general crap that gets thrown into the bottom of the car even in good climates let alone the freak Florida rain shower or sprinkler runoff that I would be paranoid about trashing my subs. I suppose if I had F/U $ and could replace them like they are a Fram air filter that would be one thing, but seriously...that design is pretty flawed in terms of reliability.


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## quality_sound (Dec 25, 2005)

If you don't treat your car like a landfill there will be very little of anything on the subs. I have 2 kids and most people think no one is ever in the car with me. Keeping it clean is not hard and will cause no problems. If it did BMW wouldn't be using an underseat location in most of their cars. 

How is rain or sprinkler runoff going to get to the bottom of the sub that's only open on the back side unless the car is upside down with the ass end facing up?


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## nismos14 (Jun 22, 2007)

Or drive in reverse all day long.


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## quiet (Feb 15, 2010)

i had a set of midbass drivers in a ported fiberglass box under the seats of a ford ranger I had about 4-5 years ago. I had no sub and had them on set up basically as a sub, forgot the xover point but it was low pass. I liked them, and lots of people would get in my truck looking for a sub box behind the seat.


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## diamondjoequimby (Jun 30, 2009)

quality_sound said:


> If you don't treat your car like a landfill there will be very little of anything on the subs. I have 2 kids and most people think no one is ever in the car with me. Keeping it clean is not hard and will cause no problems. If it did BMW wouldn't be using an underseat location in most of their cars.
> 
> How is rain or sprinkler runoff going to get to the bottom of the sub that's only open on the back side unless the car is upside down with the ass end facing up?



c'mon. Water has a tendency to go everywhere. Spray from the tire on the underside, turn left or right, water in all kinds of places.


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## BigRed (Aug 12, 2007)

I thought this was an underseat midbass thread?  I have midbass's in my floor, and I have had no issues with debris, etc.


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## HondAudio (Oct 19, 2006)

tornaido_3927 said:


> Yeah I have some shallow woofers on the way, as I don't have alot of room..
> 
> But I was wondering on specifics, I know speaker TS parameters will affect this but I'm wondering in general terms for an underseat midbass enclosure, would you go sealed or ported? If ported, which way would you fire the port? Or would you horn load it into the footwell? Etc..
> 
> Sorry if these are total noob questions.. I just haven't been able to find much specific info on this..


Maybe sealed, but vented into the ducts that route the air from behind the dash to under the seats?


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## HondAudio (Oct 19, 2006)

quality_sound said:


> The sheetmetal in the floor plays almost nopart in the car's structural integrity. Also, it not like he cut a hole and left it empty. I'll bet it's stronger now than before. Last, I'm pretty sure the car is a trailer queen.


I am not trained as an engineer, but I think if you cut a hole, sandwiched the edges with two steel rings, welded them in place, tapped holes for the sub, and then went about your normal deadening procedures, it would probably work.


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## mitchyz250f (May 14, 2005)

That's a big hole. Modern cars are desighned to collapse in a controlled manner to preserve the passenger compartment. Making a hole that size in the car will (read must) effect the strength of the chassis. Any other statement made is without foundation. Now if you reinforce it with steel rings you may correct for the loss of strength or make it too strong and effect the way the chassis crushes. Or you may correct the strength in one axis but not another. 

An engineer friend that worked for Toyota told me something he was envolved in; a ¼ hole in Tacoma frame rail was increased to ½” to accommodate the mounting of accessory step. It affected the entire way the truck reacted in an accident and another solution to mounting the accessory had to be found. Now, granted the frame rail is a more critical structure than the sheet metal under the seat. But it all adds up when they do the simulations and testing.


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## rcurley55 (Jul 6, 2005)

mitchyz250f said:


> That's a big hole. Modern cars are desighned to collapse in a controlled manner to preserve the passenger compartment. Making a hole that size in the car will (read must) effect the strength of the chassis. Any other statement made is without foundation. Now if you reinforce it with steel rings you may correct for the loss of strength or make it too strong and effect the way the chassis crushes. Or you may correct the strength in one axis but not another.


The sub floor in that car carries virtually no load - it's paper thin sheet metal. Now, you can make an argument that in an accident, the force required to bend a sheet metal floor with and without that hole in there will change - that's fine, but decide what is an isn't negligible first... 



> An engineer friend that worked for Toyota told me something he was envolved in; a ¼ hole in Tacoma frame rail was increased to ½” to accommodate the mounting of accessory step. It affected the entire way the truck reacted in an accident and another solution to mounting the accessory had to be found. Now, granted the frame rail is a more critical structure than the sheet metal under the seat. But it all adds up when they do the simulations and testing.


You can't compare a frame rail to the sheet metal floor pan :laugh:


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## mitchyz250f (May 14, 2005)

‘You can't compare a frame rail to the sheet metal floor pan’. 
This is true, but using the same argument, you can’t compare a ½” and a 10” hole either.
I think the key thing you said is’ virtually no load’. I can tell you from CAD simulations that I have run on spinal and knee implants that tiny changes in component geometry, so small that most people would consider them insignificant, can have a dramatic effect on a component failure strength and life.

I can take a steel forging that is pretty freaking strong, and introduce a small notch (we will call that a concentration factor) and dramatically affect that parts strength. The reverse is true also.

Early passenger airplanes had windows with sharp corners. This created a concentration of force at the corners of the window, and the fuselage failed. Plane broke. That is why planes now have windows with generous corner radiuses. I guess you would have said that the window carries virtually no load and left the window as is.

I have worked as a mechanical engineer for over 30 years and can tell you that simulations often reveal crazy things that commons sense cannot predict. This is why engineers in the medical device industry and automotive and aerospace industry… run simulations. The days of guessing something will not make a difference are gone, at least when people’s health and lives are at stake

My point is you don’t know how the cars chassis will react without doing a simulation. And this is a very complex simulation and would take hours if not days to run, and you just did it in your head.


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## rcurley55 (Jul 6, 2005)

mitchyz250f said:


> ‘You can't compare a frame rail to the sheet metal floor pan’.
> This is true, but using the same argument, you can’t compare a ½” and a 10” hole either.


You are right, I certainly wouldn't make that comparison - it would be pretty meaningless...



> I think the key thing you said is’ virtually no load’. I can tell you from CAD simulations that I have run on spinal and knee implants that tiny changes in component geometry, so small that most people would consider them insignificant, can have a dramatic effect on a component failure strength and life.


I've run similar simulations. I wouldn't compare a floor pan in a car to a spinal or knee implant either...



> I can take a steel forging that is pretty freaking strong, and introduce a small notch (we will call that a concentration factor) and dramatically affect that parts strength. The reverse is true also.
> 
> Early passenger airplanes had windows with sharp corners. This created a concentration of force at the corners of the window, and the fuselage failed. Plane broke. That is why planes now have windows with generous corner radiuses. *I guess you would have said that the window carries virtually no load and left the window as is.*


You have just proven that you know zero about my background or knowledge - this is engineering 101...



> I have worked as a mechanical engineer for over 30 years and can tell you that simulations often reveal crazy things that commons sense cannot predict. This is why engineers in the medical device industry and automotive and aerospace industry… run simulations. The days of guessing something will not make a difference are gone, at least when people’s health and lives are at stake
> 
> My point is you don’t know how the cars chassis will react without doing a simulation. And this is a very complex simulation and would take hours if not days to run, and you just did it in your head.


None of this is news to me, I've performed my fair share of FEA in my day as I also have an ME background.

By your logic, I'm assuming you run a simulation on every car before you ever drill a hole, remove a spare, or god forbid bolt something down? 

Somehow I doubt it.


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## quiet (Feb 15, 2010)

i agree with mitch. but can we get back to the tread about midbass instead of strength/load debates.

I would like to know if a underseat midbass would be better or worse than a kick or door midbass.

also I have a set of kicker ssmb8's, are they any good? or would they be worth adding to my system, i have Hertz HSK165 2ways in the doors.


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## tornaido_3927 (Nov 23, 2009)

HondAudio said:


> Maybe sealed, but vented into the ducts that route the air from behind the dash to under the seats?


Haha now that is the kind of thinking I like to see on here!
I doubt it'd work, but it would be awesome to see someone attempt it


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## quality_sound (Dec 25, 2005)

diamondjoequimby said:


> c'mon. Water has a tendency to go everywhere. Spray from the tire on the underside, turn left or right, water in all kinds of places.



Again, only the back side of those "pods" is open and it's only about 4" tall. That driver would likely see more water in a door than it does under the car in that "pod."


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## s4turn (Jun 17, 2009)

would it work if I had a midbass under each front seat, playing around 60hz - 250hz

or at those frequencies? does it become too directional? as my mids were be intended to play down to 250/300 hz


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## quality_sound (Dec 25, 2005)

It'll be fine. In my GTI they played up to 300Hz and they fired into the side of the front seats.


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## retroaudioinc (Jan 25, 2009)

How would something like these do under a seat and if they would be ok what size box would I need? They would be going under the seats in a chevy 2500HD so the truck it's self is very wide.

I am just not sure how big the box should be for 6.5's never built one.. LoL Is there TS specs any where online for these? I know it's a long shot but I have not been able to find any..


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## dvsadvocate (Mar 17, 2008)

retroaudioinc said:


> How would something like these do under a seat and if they would be ok what size box would I need? They would be going under the seats in a chevy 2500HD so the truck it's self is very wide.
> 
> I am just not sure how big the box should be for 6.5's never built one.. LoL Is there TS specs any where online for these? I know it's a long shot but I have not been able to find any..



Try this:
OZ-180 6.5" Midbass/Woofer
Fs = 48.71 Hz 
Re = 3.5 Ohms
Qm = 3.075 
Le = 0.42 mH 
Qe = 0.788 
Xmax = 6.0 mm
Qt = 0.627 
Pmx = 100 W 
Vas = 0.62 Ft3 
SPL= 89.94 dB

Thiele/Small Parameters


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## retroaudioinc (Jan 25, 2009)

dvsadvocate said:


> Try this:
> OZ-180 6.5" Midbass/Woofer
> Fs = 48.71 Hz
> Re = 3.5 Ohms
> ...



Sweet, do you think they would work ok? Only thinking about it since I got them sitting around..


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## dvsadvocate (Mar 17, 2008)

I think you should just give it to me. Those things are crap! Hahaha! Just kidding man. Theyd work for IB use. They should work well on the doors. The box requirement according to Bass Box Pro is about 1.063 cu. ft. so its kinda big. Try aperiodic for that. I have a 4incher that id wanna use someday. Too bad the tweeters are out of reach.


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## invecs (Jul 30, 2005)

retroaudioinc,

It depends on how big of an enclosure you can fit. 1.063 is a big enclosure. You could try targeting a box size with a qtc response of .8 then slap in an aperiodic membrane or a scan airflow resistor to bring down the box Q. I have a floor mounted midbass setup just in front of the seats in my car. I have the mids in a 0.2cuft enclosure...for most people, that enclosure is quite big already. I don't know how you could make the OZ work...they are much more suitable for freeair or in large sealed enclosures. If you are going to try, start finding drivers that can work in small sealed enclosures. It's hard if you are going to use a high qts driver in a small enclosure...you will have enclosure resonance problems.


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## retroaudioinc (Jan 25, 2009)

Ok would these be better then say a set of DDMB? Thats what I have in my doors now. I really don't do SQ much more SPL but I have always been a huge OZ fan, trying to find a way to fit them in, if I have to grab another pair I can if they would "louder" but cleaner then my DD's I have now.

It's not a good idea to mix mids right like DD's in the door and the OZ's some where else right, I should stick with one brand all OZ or DD correct or is that not true?

I am trying for LOUD and Clean..


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## thehatedguy (May 4, 2007)

DDs are going to kill the Oz in terms of output.

Could port the DDs.

Or wait on the 8" DD midbass.


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## HondAudio (Oct 19, 2006)

tornaido_3927 said:


> Haha now that is the kind of thinking I like to see on here!
> I doubt it'd work, but it would be awesome to see someone attempt it


Welcome to my thinking


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## ANDRESVELASCO (Dec 7, 2015)

Found this old thread and I have a question... 
Since I have some door rattles (no matter how much dynamat I've been used!. I lower my mids up to 70's, and when play loud I allways get some kind of rattles), I have been thinking about put a mid bass driver down passenger seat (a good one, maybe a shallow 10" elate) in a sealed enclosure. 
This way I could free some low freqs from my doors and avoid those anoying rattles. 

My question is: Would this work if I run just one driver in mono, bandpass crossed from 70 to 100 hz? (or need a stereo signal and L/R drivers to get good results? 

(thnks in avance!)


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## nismos14 (Jun 22, 2007)

Need stereo signal.


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## 1fishman (Dec 22, 2012)

ANDRESVELASCO said:


> Found this old thread and I have a question...
> Since I have some door rattles (no matter how much dynamat I've been used!. I lower my mids up to 70's, and when play loud I allways get some kind of rattles), I have been thinking about put a mid bass driver down passenger seat (a good one, maybe a shallow 10" elate) in a sealed enclosure.
> This way I could free some low freqs from my doors and avoid those anoying rattles.
> 
> ...


I don't see why you wouldn't be able to get good results. Lots of people cross their mono subs to 100hz and higher.


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## ANDRESVELASCO (Dec 7, 2015)

1fishman said:


> I don't see why you wouldn't be able to get good results. Lots of people cross their mono subs to 100hz and higher.


That's what I thougth... Putting a solid woofer that can handles 150 wrms with authority, (I don't need more than this, because my system is sq oriented, not too loud) playing at that very low mid-sub freqs (70 to 100hz), it should be unlocalizable... 

But then again... Will I be good with only one woofer (feeded in mono)? 

(looking for simplicity here and trying to save about 400 bucks of another woofer :blush: )


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## ANDRESVELASCO (Dec 7, 2015)

nismos14 said:


> Need stereo signal.


Why?


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## banshee28 (Mar 23, 2006)

dvsadvocate said:


> Steve Head aka Audionutz mounted a 10inch Oz Audio driver underneath the seat of his Civic. It was freeair and he cut a hole underneath to let the driver go through.


I have a BMW with 8's under the seat. I figured if 8's sound pretty good, 10's would be even better, so I am upgrading them to 10's!! 

So I went from the stock 8's to Morel "shallow mount" 10's. They are modified to fit in the stock enclosures, and we opened up the sheet metal of the floor to vent the speaker a little better, more like a IB install. I actually got these from another DIY member, and when I heard them in person a while back in his car, the mid-bass was "hitting you in the chest" while still very seamlessly blending in with the sound stage!. I have yet to hook them up in my install, but should have them ready in a week or so. 

I will actually have my stock 8's and enclosures for sale here soon, as well as a spare set of the Morel 10's... Maybe the ones BNIB. PM if interested. 

I plan on having the 10's play ~60-100Hz or so, and the Sub below 60Hz. Mids in the doors from 100Hz up to whatever for the tweets. Should be fun


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## ANDRESVELASCO (Dec 7, 2015)

banshee28 said:


> ... we opened up the sheet metal of the floor to vent the speaker a little better, more like a IB install...


My only concerns, are about road noise, specially on the hiway... (I'm a dialy hiway driver, so it is not for me).


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## ANDRESVELASCO (Dec 7, 2015)

banshee28 said:


> ... we opened up the sheet metal of the floor to vent the speaker a little better, more like a IB install...


My only concerns, are about road noises, specially on the hiway... (I'm a dialy hiway driver, so it is not for me).


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## 1fishman (Dec 22, 2012)

ANDRESVELASCO said:


> That's what I thougth... Putting a solid woofer that can handles 150 wrms with authority, (I don't need more than this, because my system is sq oriented, not too loud) playing at that very low mid-sub freqs (70 to 100hz), it should be unlocalizable...
> 
> But then again... Will I be good with only one woofer (feeded in mono)?
> you can't localize it
> (looking for simplicity here and trying to save about 400 bucks of another woofer :blush: )


Yes, you said it yourself you can't localize it. you'll be good with one woofer playing below 100hz same as if you had one sub playing to 100hz.


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## thehatedguy (May 4, 2007)

Kind of a waste to play 60-100 only.


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## oabeieo (Feb 22, 2015)

ANDRESVELASCO said:


> My question is: Would this work if I run just one driver in mono, bandpass crossed from 70 to 100 hz? (or need a stereo signal and L/R drivers to get good results?
> 
> (thnks in avance!)


Crossing from 70-100 is only a 30hz span. It will make sound yes but sound good??? That will be tough. 
With a 1st order filter on both sides yeah maybe with a steeper slope the *majority* of what you hear will be delayed roll off and out of time with the 30hz span. By itself no that bad when when you have speakers on both sides of the crossover it won't sound smooth. It will get loud and full the null just fine but smoothness will be a tough go to say the least.


Now get the under seat box to not have a HPF and could work very nice . Use the same exact crossover as sub and play them both to 100 and should be nice. Use eq to tame any peaks individually and can be very good


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## metanium (Feb 2, 2007)

Well since you guys resurrected this old thread, I'll chime in with my 2 pennies worth. I heard Scott Buwaldas BMW 135 at Knowledgefest a couple of months back. He's running L8SE's from 45-250Hz in the stock locations, but opened up to the outside, like AudioNutz's 10's. This car sounded phenomenal.


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## banshee28 (Mar 23, 2006)

thehatedguy said:


> Kind of a waste to play 60-100 only.


Actually great point. I am using this as a starting point since its what I figured they were previously setup as. I am definitely going to try some options. 



ANDRESVELASCO said:


> My only concerns, are about road noise, specially on the hiway... (I'm a dialy hiway driver, so it is not for me).


 Nope, the 3 circle holes I have now are like less than 2 inches each all around the bottom of the speaker magnet area, then the enclosure and speaker cover it up from there. So I think its just enough for it to breathe and should still be quiet. 



oabeieo said:


> Crossing from 70-100 is only a 30hz span. It will make sound yes but sound good??? That will be tough.
> With a 1st order filter on both sides yeah maybe with a steeper slope the *majority* of what you hear will be delayed roll off and out of time with the 30hz span. By itself no that bad when when you have speakers on both sides of the crossover it won't sound smooth. It will get loud and full the null just fine but smoothness will be a tough go to say the least.
> 
> Now get the under seat box to not have a HPF and could work very nice . Use the same exact crossover as sub and play them both to 100 and should be nice. Use eq to tame any peaks individually and can be very good


 Interesting, will have to try this! 



metanium said:


> Well since you guys resurrected this old thread, I'll chime in with my 2 pennies worth. I heard Scott Buwaldas BMW 135 at Knowledgefest a couple of months back. He's running L8SE's from 45-250Hz in the stock locations, but opened up to the outside, like AudioNutz's 10's. This car sounded phenomenal.


Great to hear!! :laugh:


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## nstaln (Feb 11, 2009)

I have dabbled with this idea…

2010 Nissan Rogue, dual JL Audio 6w3v3 4ohm.

Pics:


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## joshuak (Apr 7, 2011)

Looks pretty sweet. How do those JLS sound?

Sent from my SAMSUNG-SM-G935A using Tapatalk


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## nstaln (Feb 11, 2009)

joshuak said:


> Looks pretty sweet. How do those JLS sound?
> 
> Sent from my SAMSUNG-SM-G935A using Tapatalk


I love em…

I listen to a lot of rock and metal…for quick double-bass kind of stuff…nothing has been better.

I have them disconnected at the moment due to a limit in movement to the drivers seat…so that box is out at the moment pending some adjustments.

They are powered via the sub channel of a JL 900/5…so they see 250rms each.

Boxes are .2 cubes each sealed…punchy, accurate and keep the impact right where I want it.

Will be adding a TC Sound TC1000 15 for the sub so I haven't quite finished the tuning…by they'll be crossed somewhere around 40hz-150hz…basically to do the 'heavy lifting' in the mid-bass region.


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## Jscoyne2 (Oct 29, 2014)

dvsadvocate said:


> Steve Head aka Audionutz mounted a 10inch Oz Audio driver underneath the seat of his Civic. It was freeair and he cut a hole underneath to let the driver go through.


Is there a build log anywhere for this or perhaps more pics of the total install?


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## robtr8 (Dec 6, 2011)

Malibu ski boat has a Solo Baric under the helm, right at my feet. 

The 328 comes with 8's under the seat but they're used as little baby subs and don't sound that good. Replaced them with Jehnerts and added a 12" to the trunk. Certainly the bass improved but not the midbass. Then I added the GB40. Holy cow!

Looked for a similar approach on the TR8. Baffled the floor pan under the seats and added 10" shallows. Running them up around 125hz. Very nice.

Said to myself "OK, so that worked" while looking at the XC90. Wound up removing the middle row seats entirely and installing two GB12D4's down firing into the footwells.

https://photos.app.goo.gl/VTqVFHPNf2Uskov52

https://photos.app.goo.gl/FNEwFeezy3Di5Q392


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## Patrick Bateman (Sep 11, 2006)

I've done midbasses under the seat quite a few times.

At low frequencies, our perception of location is based on phase. Due to that, you'll want the midbasses to be as wide as possible.

I like doing bandpass boxes. Here's why:

Our car is about six feet wide. With a conventional box under the seat, we can separate the drivers by about four feet. If you go with a bandpass box, you can put the ports on the side. That allows you to separate the two sources by about five feet. That widens the stage by 25%. (From four feet to five feet.)


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## jamesjones (Mar 8, 2007)

Patrick Bateman said:


> I've done midbasses under the seat quite a few times.
> 
> At low frequencies, our perception of location is based on phase. Due to that, you'll want the midbasses to be as wide as possible.
> 
> ...


Could you post a picture of one of your bandpass setups? I can't picture in my mind how you could stuff one underneath a seat.


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## Patrick Bateman (Sep 11, 2006)

jamesjones said:


> Could you post a picture of one of your bandpass setups? I can't picture in my mind how you could stuff one underneath a seat.


My first stab at it was here : http://www.diymobileaudio.com/forum...162495-new-way-increase-soundstage-depth.html

I don't recommend copying that one. It worked, but it was insanely time consuming. Making a bandpass midbass is like making a subwoofer, except it takes twice as long because the parts are so small. It's a real p.i.t.a.

The next one was basically a circle inside of a square. The sealed part of the bandpass was in a circular enclosure, and then that was placed inside a square enclosure. I don't think I have any pics of that.

The current one I'm still working on, it's the same driver as the first link, but the enclosure is 3D printed.


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## jamesjones (Mar 8, 2007)

Patrick Bateman said:


> My first stab at it was here : http://www.diymobileaudio.com/forum...162495-new-way-increase-soundstage-depth.html
> 
> I don't recommend copying that one. It worked, but it was insanely time consuming. Making a bandpass midbass is like making a subwoofer, except it takes twice as long because the parts are so small. It's a real p.i.t.a.
> 
> ...


Thank you. You my friend are an evil genius at this stuff.


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## chithead (Mar 19, 2008)

I've used 10" subwoofers under the seats before with ok results (was new to this and didn't have them aimed properly, enclosure way too small, etc.

My most favorite setups so far though, were a pair of Diamond CM3 8" subwoofers mounted under the dash of a Dodge Ram, and then this 2005 Subaru Outback we have come with the factory optional underseat sub. While that 6.5" sucks at bass, the midbass in the car is incredible!!! I mean, real, true, kick you in the chest stuff. 

The Ram with those 8" subs was beyond realistic. Just effortless with plucks and kicks, easy to tune, and sounded so natural. Paired with Diamond Hex 5.25" woofers, was the first time I, "felt" the guitar on Van Halen's Eruption. Nirvana's Lithium, that intro would make you giggle like a kid. But then toss in Fanfare For the Common Man or Toccata and Fugue, and it was like a concert hall.


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