Comparing speaker/cab sizes
 

When talking about 10" speaker cabs vs. 15" speaker cabs, I've heard two different things in terms of how much sound they create (air that they move). Some say that a 2-10 is close to a 1-15, others say a 4-10 is close to a 1-15. ???

Its not all apples to apples here. There are a lot of specs to consider outside of driver diameter, which means little to nothing to tone of the speaker. As far as "max spl" goes if everything else is the same (it never is) then yes a 210 has around the same output as a 115.

Yes, that's all I was talking about; the output sound levels. I've thought what you said is true that the 2-10 and 1-15 are roughing equal.

I'm no expert on this subject, but I've listened to those that are. Apparently, you measure not only the surface area of the speaker, but also the distance it travels in order to make a comparison.

If everything else is equal then yes the output is similar, (its not equal though).

Displacement.

But you have to look at the balance of displacement, sensitivity, frequency response, and power handling.

All that said, you will always have more consistent results running a pair of identical cabs (i.e two 210's or two 115's).

In general a 210 is very similar to a 115 in terms of volume. A 410 dwarfs a 115.

Displacement varies from one driver to another.
For instance, a single Eminence 3010LF has almost as much displacement (305 cc) as a Basslite C2515 (381 cc).

How true. I have experimented with mixing a 2-10 with a 1-15 and a 4-10 with a 1-15. Standing close to the stack, as many of us do when we play bass, it sounds okay. But walk around and the problems with several cancellations and peaks are heard; much more than from the natural acoustics of the room. There are several threads on this here on TB. Now, I just use the 4-10 by itself and the sound is much better. The 1-15 was sold a couple of months ago.

Surface Area Chart:



210 = 157"
115 = 176"

There is a massive problem with this chart, it shows the surface area of the speaker, not the area that actually moves. Also its not really surface area that matters, its displacement (with a few other parameters).

Surface area definitely matters, but you can't take it into account without also taking the xmax of the speaker(s) into account as well.

To know how "loud" a driver is, you need to know how much air it moves. This is a cubic measurement, not a surface area measurement which is what the chart above shows.

To determine the amount of air that a driver moves, you need to multiply the surface area by the distance the cone moves back and forth. This is given in the Vd spec of a driver.

It's not a "massive problem" since the chart is only meant to show surface area - nothing else.

All else being equal, greater surface area = greater volume.

Yes, correct.

Another thing you also need to consider, though, is sensitivity. The C2515 is pretty good at 98dB SPL, but the 3010LF is low at 92.7. 5.3 dB is a significant difference in loudness. And as you mention, while the 3010LF's displacement is tremendous for a 10, the C2515 is greater by 25%. The C2515 is also $50 less, & while the C2515 isn't full range, it comes a lot closer than the 3010LF. Like any other LF driver, almost everyone would want (need?) to pair the 3010LF with a dedicated mid or tweeter, while many could likely get by with the C2515 by itself if push came to shove.

http://www.usspeaker.com/kappalite3010lf-1.htm

http://www.usspeaker.com/bass%20liteC2515-1.htm

It isn't that I'm a C2515 fanboy. Just comparing it to the 3010LF. Give me a Delta Lite II 2515 (99.2 dB, 54Hz-3.7kHz, ~410cc displacement) for $30 less than the C2515, or a Kappa Lite 3015 (100.8dB, 40Hz-4kHz, ~505cc displacement) for just $20 more than the 3010LF.

http://www.usspeaker.com/delta%20lite2515II-1.htm

http://www.usspeaker.com/Kappa%20Lite-3015-1.htm

Or a couple Faital Pros...the 15PR400 (100 dB, 35Hz-4kHz, ~460cc) or 15FH510 (98 dB, 35Hz-3.15kHz, ~748cc!). And the 15FH510 is just $195 till the end of Dec. That's a great deal.

http://www.usspeaker.com/faital%20pro%2015PR400-1.htm

http://www.usspeaker.com/faital%20pro%2015FH510-1.htm

Or if an LF is the goal, it's gotta be the Kappa Lite 3015LF (99.8 dB, 40Hz-1.5 kHz, ~855cc). Just $20 more than the 3010LF & almost triple the displacement.

http://www.usspeaker.com/Kappa%20Lite-3015lf-1.htm

In general look at the size/dimensions of the enclosure too. Usually a bigger box will have a bigger sound and deeper lows.

The chart still isn't accurate, FWIW. Actual cone diameter on a 15" speaker is more like 13.2" (or less) because of the surround. Actual cone area is closer to 137 square inches (or less). The actual cone area of a single 10" speaker (*cone* diameter around 8.3") is about 54 square inches.

Two fifteens have about the same area as five 10" speakers.

Greater surface area will usually equal greater volume until you run out of motive power in the amp. As with any piston, it takes a certain amount of power to compress a volume of air (in each direction) and at some point of speaker area you simply run out of power.

You have my apologies.

I just thought it would be helpful to the OP to know the approximate measurements of various cone areas.

But, apparently, the information is too inaccurate and incomplete to be of any use.

It seems like what you really want to know is which driver configuration (210, 115, 410) can go loudest, given adequate power. There is a wide range of max spl in each configuration. Some 210's can go louder than some 115's and 410's. So, driver size and number is a poor indicator of max spl. Chances are that there are many cabs (singly or in pairs) that will meet your spl requirements (given enough power). If you are on a tight budget (wanting to get as much spl as possible for low cost) look into used cabs or new ones from Peavey, GK (MBE) or similar.

Good luck!