SIMPLE QUESTION: Can a 10" woofer give me the same bass of a 15" one?

[tinitus]

no...unless all other variables than size are fixed

[murillollirum]

ok. thx to all here, now I will order my dinner, a lamb au sweet wine... and see the brazillian guys kick some a.. in UFC 156. Good night to all you guys.

[Cornelis Spronk]

Speakers do not produce strong sound output below their resonant frequency.

Resonance is the natural frequency of vibration of any mass attached to a spring like restoring force. For any speaker, its lowest resonant frequency is in free air. While in free air, however, the air from the back comes around and cancels the air movement from the front. This is because when the speaker is pushing the air from the front side, it is pulling the air from the back. Even while a speaker in free air may be moving a lots of air, it will not sound very loud. The pulled (low pressure) will cancel the pushed air (high pressure).

The free air resonant frequency depends on the mass of the cone, and the stiffness of parts that support the cone. If you modify the cone support system, you will change its resonance. The stiffer the the support, the higher the resonance. All other things being equal, a speaker with a foam surround will have a lower resonance that a speaker with a rubber surround. This has an advantage for good bass. However, foam breaks down more than rubber with age, and in 20 years you may have to replace the foam.
When a speaker placed in a box, the resonance is increased, because the air behind speaker acts a restoring force which has the same effect as stiffening the surround.

When a large speaker is placed in a small box, it moves more air inside the box than a smaller speaker. This gives the larger speaker the impression that the air in the box is stiffer than what the smaller speaker would experience. The net result is a larger shift in the resonance of the larger speaker, driving the resonance up more.

If a box is too small, the larger speaker is at a disadvantage. Yes, a large speaker will move more air, but not in a box that is so small as to drive its resonance up too much. Net result, its low bass output will suffer more.

[a.wayne]

Originally Posted by murillollirum

Please be honest, can a 10 inch woofer offer the same impact of bass, I'm telling of the first octave 20-40Hz of a 15 inch?
I;m asking this because of the quote of a JBL guy, MArk Gunder: "to make sound, you must move air"

I hope this is not what you are telling your wife ....

Originally Posted by Cal Weldon

Too vague of a question. It's like asking: can a truck go faster than a sportscar?

Some sportscar to be beaten by a truck ...

Originally Posted by sreten

Hi,

A really good 10" will slaughter a poor 15", it just needs around double
the xmax to do the job the same. Given your talking 20Hz to 40Hz, that
is possible in moderate volume with a lot of power with a 10". Generally
speaking a poor 15" will need a lot more box volume and less power.

However, if the 15" has about 4 times the cone mass of the 10" and
the same xmax, it will slaughter the 10", but will need a far bigger
magnet to do so, and will be commensurately much more expensive.

A good 15" will kill a good 10", depending on your design criteria.

Which it all boils down to, good design, and proper drivers for purpose.

rgds, sreten.

Agree , SPL ONLY , As Long excursion , means more distortion , when the woofer has to come from waaaaayyyy out there for the next bass note ...

Originally Posted by pdul

What became of the 30" from Fostex. I saw them in the 80s?
Two of those would make a nice sub.

In the 70's i had EV 30inchers and Hartley 24inch monsters , stupidly , I gave them away ...

[balerit]

Usually, but not always, the sensitivity of the 15 inch is higher than the 10 inch therefor it requires less power from the amplifier. The comparison you are trying to make is like saying a 4 cylinder engine is better than an 8 cylinder engine.

[tinitus]

Originally Posted by balerit

........is like saying a 4 cylinder engine is better than an 8 cylinder engine.

for fishing boats they have preferred 3 cylinders for being less hard on the wood construction

[zobsky]

Too vague a question with more detail on the specific drivers, but just to humor you,....Horn load the 10" and compare it to the 15" It's the 15 that might be trying to justify its existence

[JMFahey]

lamb au sweet wine

Ugh !! Like covering a steak with crushed Oreos and sprinkling vanilla over it.

Marinate your lamb overnight in *dry red* wine and spices before cooking and *then* maybe we'll agree.

Back to the speaker choice, *if* you are limited by size (as in designing a speaker system for a typical Living Room) a 10" speaker can easily outperform a 15" speaker, hands down.
As in way flatter response, deeper bass, smooth sound, and so on.
It will need more driving power, of course, piece of cake.

Now, if we talk live sound, such as Band PA or DJ stuff , and have no size/weight/power limitations and want highest SPL, yes, 15" are preferred over 10".

But to make a choice, the OP question must be rephrased in more precise terms.
As is, it's too vague.

[tinitus]

ok, lets take a normal 88db 10" bass/sub woofer
put in in a closed box where it rolls off at 35hz, giving -6db at 30hz

then put a 96db 15" in a closed box where it rolls off at 50hz, giving -12db at 40hz

so if you remove anything above 50hz, SPL at low frequencies could be equal for both woofers, in theory
will it happen that way in reality ? .......don't know

but man, when I look at a hifi woofer, and visually compare it to a PRO woofer, many hifi woofers look like crap

[lolo]

it's not that easy, very often the large, very high sensitivity pro woofers have a rather high Fs.