IMHO MB Quart makes as good a sub as you'd need for an sq setup. I haven't heard the Premium series, but the Reference series is damn good for the money. 12" dual 2 ohm for $80. I put one in my friends system and it gets as loud as you'd ever need it and has good crisp bass. Because of how great his sounds, I'll be getting a premium 12" for my car shortly. I'll be running basically the same setup, only my CDT's will be a little bit higher output and a little bit higher model (one of the models is $150 off on woofers right now).

Like what was mentioned earlier...the front stage is what makes or breaks your system. Before I knew anything about car audio I bought some stuff for my car and was taken in by false specs of some off brand companies (rather than showing frequency response with like +-6db, they just showed frequency response, etc). I bought Quantum Q52's for my chrysler conquest, and a 4-channel cheapo amp. I ended up putting the components in my riviera along with that amp, and my LA 10" sub. The speakers didn't sound terrible, but had nothing below 120Hz. If I set my HPF any lower than 120Hz, I would get a crap load of distortion when turned up. Therefore I had to set the LPF on the sub really high. It sounded terrible. I then bought an 8" MB Quart sub and the sub frequencies sounded a lot better, but I was still lacking those low mids and the music sounded empty.

First things to do when putting together a system...Buy a good set of components (preferably 6.5"), and an amp to power them. If there isn't enough bass for you, buy a cheapish sub and amp to fill in the bottom end. Then later you can upgrade the sub/amp.

Well, by cheap I mean, like you can get a 10" MB Quart for like $70 and it won't require a massive amp

Have you checked the enclosure size requirements for the MB Quart subs? Usually subs requiring less power tend to need a larger box to play deep.

They have the typical requirements. The 8" MB quart reference is 150 watts rms and requires .5 cubic feet, the 10" is 300 watts rms and requires .75 cubic feet, and the 12" is 500 watts rms and requires 1 cubic foot.

Hell for $200 you can get a 12" reference and a cadence amp that will more than power it. The reason I said 10" though is because with some cars you might need to upgrade alternator to run the 500 watts for the sub and another ~200 watts for your front stage. Therefore, 10" is a cheap sub that will sound great and get plenty loud.

Keep in mind that larger subs are more efficient than smaller ones - they need less power to get loud, so a 12" cone, though it may have a higher RMS power rating, doesn't actually need that extra power - it can use the same power as a 10" and will play slightly louder at that level. Very large subs, 15" and 18" sizes, can get extremely loud with only a few watts. 100 watts or so can be more than enough, although the VCs on subs this size can normally handle 500-1000W.

So, to get the most SPL with the smallest amp, pick the largest subs that will fit your application. This is often the most cost effective and low distortion route. It kind of goes against what most people think - that a big sub takes a big amp to push it. Actually, a big sub will work fine with a small amp, plus it gives you the option to feed extra power if you want to make some boom. Only drawback is large size.

Not necessarily...

I had my LA 10" sub in my cousin's car and her amp couldn't push it. I then gave her my 8" MB Quart and it sounds great. Granted it's a factory Monsoon amp, but a bigger sub does take more power to move. There is more cone to move and you do reach a point where the amp just isn't powerful enough

You're trying to compare two different sub brands/models (apples and oranges). The LA and MB really shouldn't be compared by size alone, because they are different subs having different T/S parameters, and entirely different response characteristics (The MBs are super lightweight with very high Sens). Also, those subs were loaded in different enclosure volumes. Too many variables to make the statement that in general, a bigger sub takes more power to move. To make things more fair...

If you took a 10" MB Quart (Reference) and installed it in a proportionally similar enclosure as your 8" MB (same resultant Qtc), and used the same amp, the 10" version would perform louder and play deeper and with less distortion, with identical power.

If you obtained an LA 8" sub (again, same model, different size), it would create less output, less extension, and more distortion than the 10" LA in a proportionally similar enclosure, using the same power.

When comparing subs of the same model family, using the same cone materials and coil designs, and similar suspension compliance, the cones of an 8" and 10" don't really weigh that much different. The cone is one of the lightest parts of the driver, and therefore isn't the only factor for moving mass, or efficiency. Voice coil size gets larger with bigger drivers, but so does magnet strength, which also helps increase efficiency. Suspension and dust cap design also plays a role.

One reason you'd run into the problem of not being able to "push" a larger cone sub is if that sub were in an enclosure that is too small in air volume. Solution: increase sealed volume, or go vented/bandpass. Another reason would be the sub uses a high mass cone and high compliance (low efficiency type with high power rating). In this case, pick a sub with better efficiency spec.

What really matters is this: a bigger cone pushes more sq inches of air for a given amount of power. That is why in nearly every case the SPL@1 Watt Sensitivity (efficiency) spec for larger drivers is higher than for smaller drivers. Take a for example, Kicker's different lines of subs (LA and MB Quart specs are hard to find):

Kicker Comp line:

8" SPL with 1 Watt input: 85.6 dB

10" SPL with 1 Watt input: 87.3 dB

12" SPL with 1 Watt input: 89.1 dB

15" SPL with 1 Watt input: 90.2 dB

Kicker L7 line:

8" SPL with 1 Watt input: 83.6 dB

10" SPL with 1 Watt input: 86.8 dB

12" SPL with 1 Watt input: 88.6 dB

15" SPL with 1 Watt input: 89.4 dB

Notice how the more efficient Comp line puts out higher dB/Watt than the L7 line. 1-2 dB is a significant, audible difference. We could say in general the L7s are "harder to drive" than the Comps and need more power, because their efficiency numbers are lower. We would not say, however, that a Comp 15" needs more power than a Comp 8", or that an L7 10" needs more power than an L7 15". Actually, the opposite is true. Check the specs - the Comp 15 is almost 5dB louder than the Comp 8 - and that's huge.

Looking online, I was able to find a sensitivity spec for only one MB Quart Ref sub - the 12" model (discontinued). SPL@1 Watt = 92 dB. Somewhere else I found 90 dB. Either number means the MBs are really efficient subs. One review listed really good in-car bass numbers at very low wattage. This suggests even an 8" could run decently on the low-powered Monsoon amp, but a 10" MB would do even better.

Bigger cone areas displace larger volumes of air for given amounts of power = more dB per Watt for larger drivers of a similar design.

Hmm, I was always under the impression that a smaller speaker would be more efficient.. Like for instance, the 8" MB Quart would have less resistance from the surround, where as the 10" and 12" would have a much larger surround (the piece that holds the cone down), therefore the 8" would require less power for it to move. I understand what you're saying about it pushing more air, but I still stand by my case in a high wattage sub, that an amp might be able to push a smaller sub to the point of making noise but not a bigger sub. The LA sub is in a smaller enclosure than what was recommended (to fit it behind the seat in my fiero), but I was also told that a sub in a smaller enclosure would play louder, and that a bigger enclosure is actually harder on the sub, because it's more air for it to move. That's why very few subs can handle open air setups.

It's understandable to assume what you are thinking. It sort of defies normal thought process to consider that a larger speaker makes more sound with the same wattage, but it's generally true. Outlaw SPL competitors know this because as a rule, using a few larger subs will normally make more SPL than a bigger number of smaller ones. You can get higher SPL with smaller drivers, but it takes more power to do it.

And you're right that heavy, high wattage subs require more power than lighter, low wattage designs. Sensitivity specs reflect this fact. However, for a pair of like model/brand subwoofers of different size, the larger one will almost always be a little louder and play a little lower in a proportionally like enclosures.

Very small enclosures can be louder at certain frequencies for some subs when given enough power, in certain vehicles. The reason is, the small air space behind the cone works as a spring to keep the cone from reaching max mechanical excursion before the thermal power limit is reached. Using a small box, a sub can actually accept its max thermal power without mechanical damage. Output is usually focused in the 60-80Hz range, a sweet spot for many small hatchbacks (cabin gain). The result is a very peaky hump and less very low frequency output, NOT good for SQ. In the graph below, the dotted grey line (Qtc 1.5) represents a small sealed box, or SPL alignment. Note the sharp roll off below 100Hz. Also note the peak bump in dB level:



Loading the same subwoofer driver in a slightly larger sealed box makes Qtc go down, and the response flattens out. Qtc 1.2 (purple) and 1.0 (red) are still boomy and loud, but many people like the sound of .90, as it provides a good amount of deep bass and not as much peak. Qtc .70 is considered optimum for SQ installs. I results in zero peak, and may result in a perfectly flat response down to 10-15Hz inside many vehicles. Qtc .50 is known as "critically damped", or a purist alignment. This is what I run in my car. The purist alignment starts to loose the function of the acoustic suspension, and is close to being IB (free-air). However it gives super sharp transients. The bass detail and accuracy is exceptional, but SPL is lower overall. In car, the response can actually ramp up the lower you go. Very low frequencies are possible, even with small woofers. Notice how you get more deep bass with alignments under 1.0 Qtc.

The interesting thing about the Qtc alignments is, the more you move down toward optimum SQ, the more the speaker cone is allowed to throw, because it has less "air spring" behind it. The result: power handling drops as the driver gets closer to reaching its mechanical limits (Xmax). You can't push the sub to its thermal limit, because it reaches Xmax first. If you do, you will damage it, like you pointed out sometimes happens in IB set-ups. This is why you want a big Xmax spec for a SQ sub, so you can keep pushing it in a big sealed enclosure, resulting in loud, deep, flat bass. The other approach is to go vented or bandpass, which can give more SPL and extension with less cone movement.

Personally, I prefer large sealed (.7-.5 Qtc) boxes, long-throw subs, and a decent amount of power to keep up. In my experience, nothing compares to a large sealed box for accurate bass.

kinda off topic, but were should i hook the hot wire that come from the amp, should i hook it to the battery or hot wire thats is used when you need a jump, this is my wife car 1995 buick regal

Either wire will work, taking the shortest route makes most sense.

Actually...

Quote:

Notice how the more efficient Comp line puts out higher dB/Watt than the L7 line. 1-2 dB is a significant, audible difference. We could say in general the L7s are "harder to drive" than the Comps and need more power, because their efficiency numbers are lower.

That right there is drawing the correlation that the subs with a higher Sensitivity rating are louder than those with lower ratings. You are comparing Apples to Oranges yourself this time...

If you use the number inside the same product line as a reference Im with you on it. Not when you compare one line to another though. Your right Im not arguing that, I know thats correct.

An L7 will be louder than a Comp any day, period. Providing they are both in optimal boxes with optimal power- despite what the Sensitivity rating says.

That is simply where my interjection came in.

A subs "efficiency" is absolutely meaningless. Only thing it provides is a number along with the common sense someone should have that the same exact subs with larger cones = more SPL. We both know and understand that. Outside of that the Efficiency rating is meaningless.

Quote:

You should have read it all before making your statements. If you're going to criticize someone's opinion, you ought to know what you're talking about. So you DO need to... LOL. Please, read before you write. It's embarrassing to contradict something that wasn't said in the first place. It's also a big waste of time.

Please see the above quote of what you said. it was said as I quoted it...

Quote:

If you'd actually read what I'd written, you would see that I never even hinted that sensitivity specs had anything to do with a sub's ultimate SPL, only how loud it will play at a given power level - 1W for example. 10W for example.

Actually you didnt hint to anything. If anything you didnt specify leaving it open to interpretation... Reread it and post/highlight the "hints". Maybe Im blind...

The whole point is you claim the kicker comp to be 1-2 dB louder than the kicker L7- which it is as identified by the Sensitivity spec.

Quote:

We could say in general the L7s are "harder to drive" than the Comps and need more power, because their efficiency numbers are lower

Is it so much the need more power? Or is it that they can handle more power? Its by virtue of design... Of course...

Quote:

But it's not useless! It tells us how loud a speaker is with one Watt of power. That's useful information.

Absolutely useless. If you buy a sub that can handle 1,000 WRMS and you are concerned of a rating at 1WRMS of power you need to take a breather.

Quote:

I don't care how loud my subs are at 1000W because I'm not an SPL competitor!

Well then you are not buying subs to get pure SPL or concerned about the SPL for that matter. Whatever floats your boat.

Quote:

What if I have a 50W amp and want to try and get the most from it?

Then common sense dictates you match a sub to your amp. They have WRMS ratings... Obviously you wouldnt go buy an RE XXX to run off your head unit.

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Here's what Crutchfield says about sensitivity:

Here is what I say about Crutchfield: IDIOTS

Here is why:

Quote:

The higher the number, the more efficient the subwoofer is at turning amplifier power into sound, and the louder it plays.

So right there your "experts" at Crutchfield are telling you that a sub with a higher efficiency will be louder than a sub with less efficiency.

Quote:

Still think it's useless info?

Absolutely!

Furthermore your other "expert" source is based upon general speakers, not subwoofers. The fail to take into account designs implemented to help the sub take more power. The reality for most subwoofers anymore is the new era of coils can handle the power, its the mechanical suspension with the issues. Thus all the new basket designs hitting the market over the last few years.

Next they are taking the readings at 1W/1M and quantifying that with more power.

The simple fact is at 1W/1M the sub will perform different and not a "tracked and predetermined" SPL levels if you stepped it up to 1000W/1M Simply because different designs, different materials create different subs. It doesnt take into account heat dissipation or lack of- which will alter things also.

In conclusion this all goes back to my first quote from your post. I dont agree with what you posted. Then you try to discredit what I have said saying I am contradicting myself?

Please quote my contradictions.

I have made two statements:

1) Comparing a Kicker Comp to a Kicker L7 by the Sensitivity rating on which one will be louder is an EPIC FAIL.

2) Sensitivity rating is meaningless as soon as its implied outside of the same products (just different sizes).

Im not going to argue anymore beyond that- Or on the whats been said business.

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1995 N/A, motor from an 04 Impala with replaced sensors!