# Why do we need 8in midbass?



## Jscoyne2 (Oct 29, 2014)

Whats the point of large midbasses? Does a 8 give you lower frequency extension than a 6? Obviously you can get louder on less power but power is cheap these days.


----------



## SoundAudio (Jul 5, 2016)

You don't. You'll move more air with an 8", but a 6.5" driver will do the job just fine.


----------



## brother_c (Sep 21, 2015)

Interested to hear the theories on this one...


----------



## DDFusionV2 (Jul 11, 2016)

It's simple. Just like anything else. More cone area with the same excurrsion will have more output. With midbass every db counts. 

Can a 8in play low? Yes
Will it be as loud as a 18 or the same design? Not even close.


----------



## Lycancatt (Apr 11, 2010)

an eight can make the same output as a 6.5 but usually with less excursuion so less cone break up and power compression. also, an eight will survive continued pounding on more than a six but only because they usually have larger voice coils to disapate heat better.


----------



## Jscoyne2 (Oct 29, 2014)

DDFusionV2 said:


> It's simple. Just like anything else. More cone area with the same excurrsion will have more output. With midbass every db counts.
> 
> Can a 8in play low? Yes
> Will it be as loud as a 18 or the same design? Not even close.


I guess to me the question of loud low extension midbass is rather confusing. My sub plays very well and very cleanly up to 125hz. My Mb can play down to 50hz sure but Its much easier for me to get loud in > 80hz frequencies with a large cone sub than a half sized door MB. With ITD being dominant, its not even necessary for me to cross my doors that low to get front bass.

So short of high spl systems. I dont see a point of large MB

Sent from my SGH-T999 using Tapatalk


----------



## SoundAudio (Jul 5, 2016)

Jscoyne2 said:


> I guess to me the question of loud low extension midbass is rather confusing. My sub plays very well and very cleanly up to 125hz. My Mb can play down to 50hz sure but Its much easier for me to get loud in > 80hz frequencies with a large cone sub than a half sized door MB. With ITD being dominant, its not even necessary for me to cross my doors that low to get front bass.
> 
> So short of high spl systems. I dont see a point of large MB
> 
> Sent from my SGH-T999 using Tapatalk


I think you answered your own question, and you are correct. I have always been of the camp to design your sub enclosure, pick location (and pick a sub), that you can play to 70-80hz without being localized. I usually don't go above that and a 6.5" driver can handle anything above that more than fine. 

It's all about your goals. If you are into SQ and not insane levels, you don't need an 8" mid bass. Most people who think they require one are people who want a bump in that region; not an accurate representation.


----------



## Jscoyne2 (Oct 29, 2014)

SoundAudio said:


> I think you answered your own question, and you are correct. I have always been of the camp to design your sub enclosure, pick location (and pick a sub), that you can play to 70-80hz without being localized. I usually don't go above that and a 6.5" driver can handle anything above that more than fine.
> 
> It's all about your goals. If you are into SQ and not insane levels, you don't need an 8" mid bass. Most people who think they require one are people who want a bump in that region; not an accurate representation.


Why is it that we can localize subs when they go over a certain db level even when they are perfectly time aligned? Is Itd only true up to a certain db difference or are we hearing louder harmonics and such that go into the iid range being played? 

Sent from my SGH-T999 using Tapatalk


----------



## Kenneth M (Oct 14, 2014)

Need, lol.


----------



## nineball76 (Mar 13, 2010)

I don't have the need or even desire to use an 8 in my car, but in my Ram, no way a 6.5 is big enough to fill the entire cabin, and get over the 5" turbo back straight exhaust.


----------



## SkizeR (Apr 19, 2011)

More cone area means less excursion needed for desired output which means less distortion. Also, more output when needed

Sent from my SM-G920V using Tapatalk


----------



## gijoe (Mar 25, 2008)

Jscoyne2 said:


> Why is it that we can localize subs when they go over a certain db level even when they are perfectly time aligned? Is Itd only true up to a certain db difference or are we hearing louder harmonics and such that go into the iid range being played?
> 
> Sent from my SGH-T999 using Tapatalk


Below about 100hz, we don't localize them, regardless of the output. What is likely happening, is that as you turn up the volume, you are also making the harmonics louder. So, the 80hz fundamental isn't localizable, but the 160hz, 240hz, 320hz, etc. harmonics are. Also, rattles are not our friend. Even if the response of the subwoofer is non-localizable, as soon as the panels behind you get excited and start to make their own noise, the sub seems localizable simply because the noise corresponds with the subwoofer's output.


----------



## thehatedguy (May 4, 2007)

I use 8s, but proaudio 8s for the extra sensitivity to mate up with some horns. The 8s I use normally aren't very bottom end heavy as they were designed more for midrange in their intended applications. 

That and I like the sound of a larger speaker playing into the midrange.


----------



## halfstock (Oct 25, 2012)

Two words: reduced strain

I'd go with a 15" midbass if I had the room.


----------



## Drop11 (Jul 4, 2016)

Why 8 inch mid bass? Cause bass in your face.

I hate my sub playing anything close to 80hz. For a pure sq tune no they are not needed and some 6.5s play lower than others but I have yet to own a pair. I really like sq speakers for their top end but they don't do so well down low without a some help. 
I have a pair of 8"s coupled with a 1" tweeter at home. They hit me in the chest from across the room. This is my favorite part of music. You can kind of mimic it with good sub integration but having your midbass play down to around 60hz with real authority is amazing. It's how my last car was setup. I'm almost to the point now where I'm about to say screw it and start cutting on my truck.


----------



## SkizeR (Apr 19, 2011)

Drop11 said:


> Why 8 inch mid bass? Cause bass in your face.
> 
> I hate my sub playing anything close to 80hz. For a pure sq tune no they are not needed and some 6.5s play lower than others but I have yet to own a pair. I really like sq speakers for their top end but they don't do so well down low without a some help.
> I have a pair of 8"s coupled with a 1" tweeter at home. They hit me in the chest from across the room. This is my favorite part of music. You can kind of mimic it with good sub integration but having your midbass play down to around 60hz with real authority is amazing. It's how my last car was setup. I'm almost to the point now where I'm about to say screw it and start cutting on my truck.


but at the same time, you really dont need a midbass playing lower than 80hz. 99% of the time the sub plays under 80hz or even under 100 better than midbass. less distortion, less rattles from the doors, etc etc. if your worried about localization, dont be. when doing sweeps, my sub sounded like it was on my dash from 30hz up to 300+ (wherever helix dsp's highest sub crossover is)


----------



## Jscoyne2 (Oct 29, 2014)

I think tactile and psychoacoustics play a big role. I can feel the bass coming from behind me because it hits my seat and vibrates the seat. If I lift my back from the seat. I get the full front bass effect. This could be remedied by having the bass actually come from the front

Sent from my SGH-T999 using Tapatalk


----------



## SkizeR (Apr 19, 2011)

Jscoyne2 said:


> I think tactile and psychoacoustics play a big role. I can feel the bass coming from behind me because it hits my seat and vibrates the seat. If I lift my back from the seat. I get the full front bass effect. This could be remedied by having the bass actually come from the front
> 
> Sent from my SGH-T999 using Tapatalk


that may be a solution, but having that bass come from the doors isnt a good solution. trust me. my doors are as solid as they come and the steel of the doors is much thicker than newer cars. And add the fact that i didnt even have the door cards on so that will be a whole other batter with resonance and vibration. at high volume, anything below 150hz flexes the outer skin of the door and causes all of the small pieces of the door, window, and locks to vibrate. theres no beating it. TLDR, i never recommend having anything in the door playing below 80hz


----------



## thehatedguy (May 4, 2007)

It will still vibrate your seat, and make you think it is coming from behind you even though the sub is in front.

Had that happen a few times when I tried subs in front when I was competing.


----------



## halfstock (Oct 25, 2012)

I think 60 Hz is really the magic number when it comes to impact. I've seen Patrick Bateman say it, I've seen pro audio guys on prosound forums say it, I've seen countless others say it. That kick in the chest is centered around 60-63 Hz. Personally, I'd rather have the drivers upfront pumping that out rather than subs that are mounted in the rear.

I know people claim that driver location doesn't really matter for frequencies that low, but I tend to disagree. Have you ever heard or seen someone say that their door mounted midbasses makes their pant legs flap but they don't really feel it in their chest? Think about that for a minute. That's air from low frequencies causing that. If it's making pant legs flap, why can't it be felt in the chest? I'd be willing to bet if those same midbass drivers were mounted at chest level, you'd be feeling that in the chest rather than in the legs. The point I'm trying to make is location matters! Even for lower frequencies like 60 Hz.


----------



## Jscoyne2 (Oct 29, 2014)

thehatedguy said:


> It will still vibrate your seat, and make you think it is coming from behind you even though the sub is in front.
> 
> Had that happen a few times when I tried subs in front when I was competing.


I wonder if rebuilding seats to absorb the vibration would add or take away from the positive experience.


----------



## Jscoyne2 (Oct 29, 2014)

halfstock said:


> I think 60 Hz is really the magic number when it comes to impact. I've seen Patrick Bateman say it, I've seen pro audio guys on prosound forums say it, I've seen countless others say it. That kick in the chest is centered around 60-63 Hz. Personally, I'd rather have the drivers upfront pumping that out rather than subs that are mounted in the rear.
> 
> I know people claim that driver location doesn't really matter for frequencies that low, but I tend to disagree. Have you ever heard or seen someone say that their door mounted midbasses makes their pant legs flap but they don't really feel it in their chest? Think about that for a minute. That's air from low frequencies causing that. If it's making pant legs flap, why can't it be felt in the chest? I'd be willing to bet if those same midbass drivers were mounted at chest level, you'd be feeling that in the chest rather than in the legs. The point I'm trying to make is location matters! Even for lower frequencies like 60 Hz.


A sub is mounted higher, near your chest if you look at it from a y axis. It is rather weird to me that you can feel it moving your pants(my tm65s do this) but you dont really feel anything else.


----------



## SkizeR (Apr 19, 2011)

halfstock said:


> I think 60 Hz is really the magic number when it comes to impact. I've seen Patrick Bateman say it, I've seen pro audio guys on prosound forums say it, I've seen countless others say it. That kick in the chest is centered around 60-63 Hz. Personally, I'd rather have the drivers upfront pumping that out rather than subs that are mounted in the rear.
> 
> I know people claim that driver location doesn't really matter for frequencies that low, but I tend to disagree. Have you ever heard or seen someone say that their door mounted midbasses makes their pant legs flap but they don't really feel it in their chest? Think about that for a minute. That's air from low frequencies causing that. If it's making pant legs flap, why can't it be felt in the chest? I'd be willing to bet if those same midbass drivers were mounted at chest level, you'd be feeling that in the chest rather than in the legs. The point I'm trying to make is location matters! Even for lower frequencies like 60 Hz.
> 
> ...


try it yourself. doesnt matter how many people say it. try it. but really, ive never seen a midbass mounted at chest high levels but have heard plenty that kick you in the chest. mine certainly do. i will say that in almost all cars, the kick panel is the best location for midbass. no rattles or resonance from the doors, and you can get a true infinite baffle. also, lets not forget that a kick drums fundamental is WAY over 60hz. just something to think about


----------



## Jscoyne2 (Oct 29, 2014)

SkizeR said:


> try it yourself. doesnt matter how many people say it. try it. but really, ive never seen a midbass mounted at chest high levels but have heard plenty that kick you in the chest. mine certainly do. i will say that in almost all cars, the kick panel is the best location for midbass. no rattles or resonance from the doors, and you can get a true infinite baffle. also, lets not forget that a kick drums fundamental is WAY over 60hz. just something to think about


You talking about IB kickpanel where its vented outside? 

Sent from my SGH-T999 using Tapatalk


----------



## thehatedguy (May 4, 2007)

Add to.

The famous Speaker Works/Richard Clark Grand National had about 300 pounds of mass added to each seat (from memory) to stop energy transfer to the body...which would come in handy since they were running rear quarter panel mounted 12" midbasses and 15s behind you.




Jscoyne2 said:


> I wonder if rebuilding seats to absorb the vibration would add or take away from the positive experience.


----------



## halfstock (Oct 25, 2012)

Just trying to wrap my head around the pants flap thing. It seems like it has something to do with being directly in front of the midbass. Think of a fan. When the fan is blowing towards you, you feel the air. When you step out of its line of sight, you don't. Same theory.

The only way I can try this out is in a home system. No way for me to try it out in my car.


----------



## Drop11 (Jul 4, 2016)

Some of you are getting very very close to understanding where I'm coming from even if you don't realize it.

60 to 100 hz FEELS different when it's coming from in front of you. The full body of drums hits you how it would naturally if you were standing in front of a drumset. 
I used to dj and have attended huge raves. That feeling of standing dead center of 2 stacks 60ft tall can't be replicated with a sub playing that high. There just isn't that much pressure in a large room. You don't really feel anything at all in your back but your front feels every note. What your ears hear is very different. You system can have beautiful Balance and fantastic sub integration but that feeling of being hit in the chest is something else entirely. Really well tuned cars do get really close. It's just not the same.


----------



## gijoe (Mar 25, 2008)

Drop11 said:


> Some of you are getting very very close to understanding where I'm coming from even if you don't realize it.
> 
> 60 to 100 hz FEELS different when it's coming from in front of you. The full body of drums hits you how it would naturally if you were standing in front of a drumset.
> I used to dj and have attended huge raves. That feeling of standing dead center of 2 stacks 60ft tall can't be replicated with a sub playing that low. There just isn't that much pressure in a large room. You don't really feel anything at all in your back but your front feels every note. What your ears hear is very different. You system can have beautiful Balance and fantastic sub integration but that feeling of being hit in the chest is something else entirely. Really well tuned cars do get really close. It's just not the same.


Since 60hz isn't localizable, the sound itself is no different from in front, or behind the listener. I'd rather have 60hz coming from my subs because they can do it with MUCH more authority than any midwoofer out there. My subs are very low distortion, so I'm not as worried about the harmonics as some people should be. I've also tackled every damn rattle and panel vibration that I could to keep those sounds from drawing my attention rearward.

With proper integration with the midwoofers and tweeters, you can get the impact from the large woofer behind you, while the front speakers play the harmonics and anchor the sound up front.


----------



## halfstock (Oct 25, 2012)

gijoe said:


> Since 60hz isn't localizable, the sound itself is no different from in front, or behind the listener.


60 Hz itself might not be localizable but most people aren't driving around listening to 60 Hz sine waves. Crossovers aren't brick walls. Frequencies above 60 Hz are still coming through the subs.


----------



## gijoe (Mar 25, 2008)

halfstock said:


> 60 Hz itself might not be localizable but most people aren't driving around listening to 60 Hz sine waves. Crossovers aren't brick walls. Frequencies above 60 Hz are still coming through the subs.


I'm aware of that, but localization doesn't really become an issue until an octave above that. If you've got a 12db/octave slope, by the time 120hz comes around it's a full 12db lower than the fundamental, and all other harmonics are even lower.


----------



## Drop11 (Jul 4, 2016)

gijoe said:


> Drop11 said:
> 
> 
> > Some of you are getting very very close to understanding where I'm coming from even if you don't realize it.
> ...


It's not that I can or can't hear where it's coming from. It's about feeling that split second of a moment that the sound hits you. If you ever get the chance, or maybe you have, get to an event early and center yourself on the stage during sound check before the place fills up with people. 
Yeah the sound we hear can be localized by our ears but really music is felt as much as heard and while we have all kinds of neat tricks to create illusions to fool our ears they are still illusions and don't feel right.


----------



## SkizeR (Apr 19, 2011)

halfstock said:


> 60 Hz itself might not be localizable but most people aren't driving around listening to 60 Hz sine waves. Crossovers aren't brick walls. Frequencies above 60 Hz are still coming through the subs.


idk if you way my reply before, but when i was doing sweeps last night on my sub, they sounded right on my dash up to 300+ hz with the crossovers wide open. people tend to not realize how high you can play subs without them bringing the sound to the rear


----------



## gijoe (Mar 25, 2008)

SkizeR said:


> idk if you way my reply before, but when i was doing sweeps last night on my sub, they sounded right on my dash up to 300+ hz with the crossovers wide open. people tend to not realize how high you can play subs without them bringing the sound to the rear


Assuming the TA is good, and the rattles are dealt with, I absolutely agree. I don't understand why people push their 6.5's so hard by trying to get 50-60hz out of them at high volumes (adding gobs of distortion) when their subs can handle it flawlessly.


----------



## SkizeR (Apr 19, 2011)

gijoe said:


> Assuming the TA is good, and the rattles are dealt with, I absolutely agree. I don't understand why people push their 6.5's so hard by trying to get 50-60hz out of them at high volumes (adding gobs of distortion) when their subs can handle it flawlessly.


but heres the thing, it was only the subs playing. TA was 100% irrelevant. it kinda freaked me out a bit to be honest. and yes, rattles were the only thing to draw it back. which is why i said 30-300hz before, not 20-300hz.


----------



## halfstock (Oct 25, 2012)

SkizeR said:


> but heres the thing, it was only the subs playing. TA was 100% irrelevant. it kinda freaked me out a bit to be honest. and yes, rattles were the only thing to draw it back. which is why i said 30-300hz before, not 20-300hz.


Try the same thing but with music. I don't disagree that a 60 Hz, or even a 300 Hz tone cannot be localized. But in the real world where people are listening to music it's entirely different.

It has a lot to do with the crossovers. Like I said, they aren't brick walls. The more you turn your volume up, the more the high frequencies show themselves through the sub. So the frequencies that _are_ truly localizable are becoming more and more audible. Now, if you're listening at lower volumes, then yeah, those frequencies won't be that audible.

Besides the crossovers, I feel that the sub's inductance plays a part in it as well. People advocate using subs with lower inductance, but I personally find that backwards if you are using subs in the rear. Think about it this way: lower inductance means the sub can play the higher frequencies better (read: more clear and defined) than a sub with high inductance. After all, inductance is basically a 6dB low pass crossover, if I remember correctly. So wouldn't it make more sense to use a sub with high inductance if you are using rear mounted subs?


----------



## brother_c (Sep 21, 2015)

Jscoyne2 said:


> I think tactile and psychoacoustics play a big role. I can feel the bass coming from behind me because it hits my seat and vibrates the seat. If I lift my back from the seat. I get the full front bass effect. This could be remedied by having the bass actually come from the front
> 
> Sent from my SGH-T999 using Tapatalk


Same here, on my personal vehicle I can place my sub anywhere behind the front seats and it feels like it is coupled to the sub. On my work truck, I have a small sub thats right behind the seat placed with the driver lining up center of the stage (right edge of drivers seat). Sound quality isn't great it's a cheap 8"sub, but it keeps the stage from shifting around.


----------



## Alrojoca (Oct 5, 2012)

A simple general answer or application to the OP would be:

In a 3 way system if no sub is placed in the front and 4" or bigger mids are used on the A pillars with the tweeters, An 8" should be used on the doors or preferably the kick panels, to really take a good 2 way or 3 way front system with a sub in the rear part of the vehicle, to the next level in SQ.


----------



## Jscoyne2 (Oct 29, 2014)

Alrojoca said:


> A simple general answer or application to the OP would be:
> 
> In a 3 way system if no sub is placed in the front and 4" or bigger mids are used on the A pillars with the tweeters, An 8" should be used on the doors or preferably the kick panels, to really take a good 2 way or 3 way front system with a sub in the rear part of the vehicle, to the next level in SQ.


Because?

Sent from my SGH-T999 using Tapatalk


----------



## Alrojoca (Oct 5, 2012)

Jscoyne2 said:


> Because?
> 
> Sent from my SGH-T999 using Tapatalk



If you really want to take it to the next level as I mentioned and depending on what you have. Actually You don't need 8"s

You only need a 5 1/4" mid on your dash or A pillar with a 10" sub in the front for a good stage and above average SQ. based on what I've seen. no 8"s needed in that set up, the sub at front will play all midbass up to 120-140hz or higher the 5"s pick up the rest from there. 

And in the case you have subs in the back, and 4-5" on the dash or A pillars, the 8"s in the front will make the tuning easier, for an all at front stage and less bass detected from the back and crossed lower than most will cross 10"s and 12"'s.


----------



## Drop11 (Jul 4, 2016)

I've been toying with the idea of a foot well mounted sub. I wish I could hear one close by. Seems like it could work pretty damned well.


----------



## dumdum (Feb 27, 2007)

Jscoyne2 said:


> Why is it that we can localize subs when they go over a certain db level even when they are perfectly time aligned? Is Itd only true up to a certain db difference or are we hearing louder harmonics and such that go into the iid range being played?
> 
> Sent from my SGH-T999 using Tapatalk


They aren’t perfectly tine aligned and level matched at the crossover, my subs in Fanta my sq car are time aligned with settings you’d never get with a tape measure or guess… same goes for the midbass under the front seats


----------



## Jscoyne2 (Oct 29, 2014)

dumdum said:


> They aren’t perfectly tine aligned and level matched at the crossover, my subs in Fanta my sq car are time aligned with settings you’d never get with a tape measure or guess… same goes for the midbass under the front seats


5 years later

Sent from my XT1710-02 using Tapatalk


----------



## dumdum (Feb 27, 2007)

Late post delete


----------



## dumdum (Feb 27, 2007)

Jscoyne2 said:


> 5 years later
> 
> Sent from my XT1710-02 using Tapatalk


Haha, didn’t even notice 🙈


----------



## dumdum (Feb 27, 2007)

Jscoyne2 said:


> 5 years later
> 
> Sent from my XT1710-02 using Tapatalk


It’s a lot of time alignment that 😉


----------



## clange2485 (Dec 10, 2020)

dumdum said:


> They aren’t perfectly tine aligned and level matched at the crossover, my subs in Fanta my sq car are time aligned with settings you’d never get with a tape measure or guess… same goes for the midbass under the front seats



Thanks for bringing it back to life though, it was interesting to read.


----------



## 03blueSI (Feb 5, 2006)

From my experience in my civic it wasn’t about lower extension but about moving air. When a kick drum hit you felt it. More of a feeling of being there at a live show


----------

