mid bass speaker efficiency

[Beatin' 10+ year member]

How well can they play between 100-200hz?

Being that my door speakers are mid-range in design, I have my 15's playing up to 150hz, where it starts to roll off. When they play notes over 100hz, you can feel it in your chest, arm hair, etc. But this is while I am feeding them around 300-500wrms together.

Is it possible to have a couple 6.5's get the same db output in those frequencies for less power?

I notice that many amps can't put out much over 100wrms at 4ohms, which nearly all mid bass car speaker resistance is. They don't make them at 2ohms to get more clean power from the amps.

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[keep_hope_alive Premium Member]

no, you won't that that kind of output from a 6.5" speaker.

you can get good midbass output in 6.5" but not what a 15" can do.

 

[Beatin' 10+ year member]

what about 8 and 10inch mid bass woofers? I'd imagine a dedicated mid bass woofer will play 100hz+ much more efficiently watt per watt than a sub woofer, but could it ever get to that point where you can feel the mid bass through out the car with only 100watts?

 

[Trey803 5,000+ posts]

depends on your setup.

You can buy some beefy 6.5's made for sealed enclosures that will take 100 rms or more.

But it will probably cost more to do it that way as compared to having your subwoofer hitting that freq range

 

[Trey803 5,000+ posts]

the frequency range in question is the typical area where people introduce another drive into the sound stage; because of this the options and opinions will never end

 

[trumpet 5,000+ posts]

The most basic way to look at this is how much air is being moved. To make a smaller cone move the same amount of air you have to have throw and acceleration. Your 15" subwoofer can play 100 Hz loudly with ease because it barely needs to move. Try to get that same output from a 6.5" woofer and it has to move a lot farther. Then you fight panel vibrations, cancellation, and on and on. Now you're into the game of choosing your compromises.

 

[Trey803 5,000+ posts]

The most basic way to look at this is how much air is being moved. To make a smaller cone move the same amount of air you have to have throw and acceleration. Your 15" subwoofer can play 100 Hz loudly with ease because it barely needs to move. Try to get that same output from a 6.5" woofer and it has to move a lot farther. Then you fight panel vibrations, cancellation, and on and on. Now you're into the game of choosing your compromises.

yes but,

the frequency range we are talking about 100-200 does not require massive air movement like 30 hz requires.

Take a tweeter for example, could be extremely loud with very little air movement.

100-200 hz is close to the crossover point from sub woofers to woofers (aka the bottom of the mid range). You could achieve similar results with both setups but most car audio subwoofer are not designed to have a flat frequency response above 80-100 hz.

Just depends on what your trying to achieve, my general answer is that you will accomplish your goal for less money and trouble using your subwoofer than you would trying to get this with a mid-woofer

 

[trumpet 5,000+ posts]

There still needs to be enough pressure to hear 100 Hz as loudly as 30 Hz.

yes but,
the frequency range we are talking about 100-200 does not require massive air movement like 30 hz requires.

 

[Trey803 5,000+ posts]

There still needs to be enough pressure to hear 100 Hz as loudly as 30 Hz.

agreed.

tats why i own an RTA an a Dayton calibrated mic

 

[Beatin' 10+ year member]

jeez I didn't know this is so difficult. My intent in the long run is to have a 4th order setup for my subs to achieve 0db reference level at around 100hz and drop off sharply above that. I'm trying to gain mega efficiency below 100hz with the subs and trying to make up for the loss above 100hz the most economical way possible using mid bass drivers.

 

[Trey803 5,000+ posts]

you're gonna want decent drivers, there are many models that will handle the watts you will needs. Also you will probably want a sealed enclosure for the mid-woofer.

If you want to talk about reference levels, buy an RTA and a calibrated mic. This will allow you to see your levels of each frequency. The pink noise is what you want to play to see this.

 

[T3mpest 10+ year member]

100hz and up can be done from front speakers. OP you need to go with pro audio speakers. As others have said, it's hard to get regular components to get that loud due to the amount of power they can take. 100hz and up isn't about excursion as much as it is powerhandling and effeciency. Each time you drop on octave, excursion goes down by 4x. So a sub moving 40mm at 30hz, to maintain output needs to move 1/4 the distance at 60hz, so 10mm. Go up ANOTHER octave to 120 and your looking at 2.25mm of excursion! The things working against you here, is a sub is generally a bigger driver and the output is too high in terms of power. If your components are 88db/1w/1m, normal in car audio, if your midbass needs to be in the 120db, then you need to gain 30 db, that's 1000 watts of power you'd need! Pro audio speakers are in the realm of 95db/1w/1m. So they are at least 6db more effecient, divide 1000/2/2 and you get 250 watts. That's ALOT more reasonable, don't you think? Step up to 8's and you can get as high as 98db/1w/1m, so only 125ish watts, with more cone area too boot! So anywhere that cone excursion isn't the limiting factor, usually 100hz and up, you'll have enough output out of effecient mids to keep up. The one thing they wont' do is play down to 60hz where many people cross over their subs. That's not what you do anyway and since you seem to want what actual midbass is 80-250hz (not 80 and down rattling your doors up front like alot of people prefer) then you'll find good pro audio speakers on some high power will be the best way to go.

Best way to do what you want. Get some pro audio 8's a big full range amp something that does at least 250 watts at 4ohms and build kickpanels. That will get rid of the buzzing doors and panel issue. If you can't do that, do the door, just make sure you treat it, it's going to rattle your doors, that's just the price you pay for being that loud in the mid bass.

My last setup was 8's in the kicks off an ARC 2500xxk, around 125-150 watts at 8 ohms. Speakers were the BMS 8 neo model. 97db/1w/1m. Very clean up to as high as you really wanted to run it, I had horns so I crossed over at 1.2k or so IIRC. Subs were VERY low distortion up high with moderate effeciency, they could play up to 2000hz if you mounted them somewhere to do it lol at 90db/1w/1m. The trunk muffled output above 120hz sharply, so I crossed over right there. I could run the focal drums tracks at reference levels with no breakup, imagine standing next to a live drum kit. Disturbed and things like that with some strong kickdrums could move your hair and clothes and still sound balanced. Midbasses made the floor rattle enough to make your feet go numb, even though the kicks until I really deadened the floors. Regardless, you could still feel them vibrate the leather seats at 150ishhz. If you can get 3-6mm of excursion on your midbass, you have enough for what you want to do. I think my BMS only had 4 and the only time I could tell they were beginning to run out of throw was at 80hz at 24db/octave. I could cross at 120 or 100 and not notice a huge difference, 80hz was only a problem with the volume CRANKED too.

Anyway, for your substage a 4th order probably isn't the way to go. I'd be looking more at a 6th order if you want your subs to play up high and down low well, but aren't awfully concerned about playing 45hz WAY louder than everything else.

 

[Beatin' 10+ year member]

I'm thinking about putting some 6x9's on the rear deck again and sealing them from the trunk using a homemade "cone" enclosure, to keep the subs from messing with them as they play.

i used to have 6x9's as factory infinity speakers and they played a mean mid bass off of 40watts each firing into the cabin.

 

[kramer_212 10+ year member]

Ive made pods before that have had 6.5in mid-basses play down to 63hertz on my rta, and still have output, depends on the install, vehicle, and position, and a bunch of other factors of coarse, if you have the room to do a 8 inch mid-bass why not the more cone area the merrier, but would highly recommend, having a 3-4 inch mid-range speaker to clear up the voices, etc...

 

[keep_hope_alive Premium Member]

rear door midbass can work very well.