Thinking about speaker sizes - why do we have the sizes we do ?

pfschim · #1 03-22-2010, 04:15 PM

Most common speaker sizes - 8", 10", 12", 15", with some variants both larger (18" and 21") and smaller (6" and 5.5" mid drivers), but very much less common in typical bass cabinet construction.

So, why is this? Why not 11", or 16" etc.

For example, for the seekers of small/light cabs, would it be possible to have most of the impact of a 12" passive radiator cab (like the Mesa Walkabout cab), but using an 11" driver ? It could be even smaller/lighter than the 12 (smaller size, lighter cage, lighter magnet etc.), but still deliver 90% of the performance of a 12".

Is this just some sort of evolved standard for manufacturing, or is there some audio/physics reason for these common cone dimensions ?

Just wondering

Tim C. · #2 03-22-2010, 04:18 PM

...It makes sense to have a standardized, specialized product?

We have all the speaker sizes we'll ever need. Not much else to it.

Matt Dean · #3 03-22-2010, 04:19 PM

I think it's because the American mind can't handle odd numbers... it makes us feel uncomfortable.

Let It Fall · #4 03-22-2010, 04:20 PM

yea but he is kinda right..

why 6-8-10-12- 15 -18-20-22-24

Tim C. · #5 03-22-2010, 04:24 PM

Quote:

Originally Posted by Let It Fall

why 6-8-10-12- 15 -18-20-22-24

The increments make sense?

A speaker's size alone does not tell you much about how it will sound or how much power it will handle. Specific design paramaters do - speakers are specialized for certain uses and we have everything we need size-wise for any acoustical application imaginable.

BigOldHarry · #6 03-22-2010, 04:25 PM

Why not metric?

This is something that has long puzzled me about guns. When choosing a handgun, you either pick a metric or standard measurement for ammo... But why?

And why are some field guns the same way? Shipboard guns are always in inches, but field guns are in MM.

What up wit dat?

Tim C. · #7 03-22-2010, 04:27 PM

Quote:

Originally Posted by BigOldHarry

Why not metric?

Most speakers do have metric measurements available from the manufacturers.

Destructobot · #8 03-22-2010, 04:47 PM

I'm glad it hasn't changed in 50 years - it means you can easily find modern built speakers to fit any amp or cab.

lunarpollen · #9 03-22-2010, 05:02 PM

It's just common practical sense to have standard incremental sizes. Just like milk, you can get a half-pint, a pint, a quart, a half-gallon, a gallon. It would be silly to ask "why don't they make 3.8 quarts, or 1.3 pints, or 2/3 gallon?"

As for handgun cartdriges, the measurements have to do with where they were designed. And for most cartriges, there are both metric and standard measurements that are recognized (12.7 mm = .50 caliber, 7.62 mm = .30 caliber). And often, a standard caliber figure isn't even exactly correct (i.e., the number that is the official "name" of the round doesn't quite match the actual diameter of the round). With artillery measurements, it depends on who originally designed it. Weight is another measurement not used much anymore for cannons, mortars, etc. 8-pounders, 12-pounders, etc.

pfschim · #10 03-22-2010, 06:08 PM

ok, glad to see the topic driving discussion. But I was not questioning standardization at all. I understand why that's a good thing for manufacturers and consumers. Nor am I getting into the sticky mess that is the sound/power/freq range debate on drivers (as in "10's are tighter than 15s" or "15s deliver more low end"). I am also not saying that the currently available sizes don't work well; I am a big fan of 15s for example.

I was asking a straight forward question: is there some known reason why speakers are the sizes they are. In other words, is there a specific reason (acoustics/physics) for a 15" driver instead of say a 14" driver, or an 11" driver instead of 10" or 12" ?

again, just curious. It's entirely possible that it was just an evolved standard that does not have any further physical or scientific rationale.

billfitzmaurice · #11 03-22-2010, 06:19 PM

Quote:

Originally Posted by pfschim

So, why is this? Why not 11", or 16" etc.

Marketing appeal.
Starting with 4 inch multiply by 1.25, then round to the nearest whole number, repeat.
4 x 1.25 = 5
5 x 1.25 = 6.25
6 x 1.25 = 7.5 , though most sixes are actually 6.5s.
8 x 1.25 = 10
10 x 1.25 = 12.5
12 x 1.25 = 15
15 x 1.25 = 18.75, but a 19 just didn't have sales appeal.

From an engineering standpoint half as many sizes would have been sufficient.

duderasta · #12 03-22-2010, 06:26 PM

Hehe I had a pioneer stereo that had 16" woofers in the main speakers

lbwdog · #13 03-22-2010, 07:13 PM

"Why Is There Air?"

Munjibunga · #14 03-22-2010, 07:18 PM

Quote:

Originally Posted by pfschim

ok, glad to see the topic driving discussion. But I was not questioning standardization at all. I understand why that's a good thing for manufacturers and consumers. Nor am I getting into the sticky mess that is the sound/power/freq range debate on drivers (as in "10's are tighter than 15s" or "15s deliver more low end"). I am also not saying that the currently available sizes don't work well; I am a big fan of 15s for example.

I was asking a straight forward question: is there some known reason why speakers are the sizes they are. In other words, is there a specific reason (acoustics/physics) for a 15" driver instead of say a 14" driver, or an 11" driver instead of 10" or 12" ?

again, just curious. It's entirely possible that it was just an evolved standard that does not have any further physical or scientific rationale.

Is there a reason to make non-standard sizes of speaker? Would an 11-inch speaker be a significant improvement over a 10-inch or 12-inch speaker? Maybe a better question would be, "Why would anyone make an 11-inch speaker?"

pfschim · #15 03-22-2010, 08:11 PM

Quote:

Originally Posted by Munjibunga

Is there a reason to make non-standard sizes of speaker? Would an 11-inch speaker be a significant improvement over a 10-inch or 12-inch speaker? Maybe a better question would be, "Why would anyone make an 11-inch speaker?"

fair enough, but I'm really not asking if we should have, say, 11" speakers, I'd say that the question is: why are 8,10,12,15 the "standard sizes" in the first place .. who or what decided that to be the standard. A corollary question could be: why isn't 11,14 or 16 the standard size for speakers instead of 10,12,15 ?

inquiring minds want to know

p.s. I'm thinking that BFMs answer is probably the right one. That there is no real acoustic/physics based reason, it just happened that way somehow and that the industry just fixed on those particular sizes.

Tim C. · #16 03-22-2010, 08:16 PM

Quote:

Originally Posted by pfschim

p.s. I'm thinking that BFMs answer is probably the right one. That there is no real acoustic/physics based reason, it just happened that way somehow and that the industry just fixed on those particular sizes.

Way back when, cabinet manufacturers said to themselves "Hey, I'll bet if we market 10"s as being tighter than 15"s, 12"s as being between 10"s and 15"s, and 15"s as having more low end than 10"s, everybody will believe us and we'll sell more products!"

Well, they were right.

billfitzmaurice · #17 03-22-2010, 08:33 PM

Quote:

Originally Posted by Tim C.

Way back when, cabinet manufacturers said to themselves "Hey, I'll bet if we market 10"s as being tighter than 15"s, 12"s as being between 10"s and 15"s, and 15"s as having more low end than 10"s, everybody will believe us and we'll sell more products!"

Well, they were right.

Standard speaker sizes pre-date musical instrument drivers by about 25 years.

Tim C. · #18 03-22-2010, 08:58 PM

Quote:

Originally Posted by billfitzmaurice

Standard speaker sizes pre-date musical instrument drivers by about 25 years.

Of course they do.

billfitzmaurice · #19 03-22-2010, 09:08 PM

Quote:

Originally Posted by Tim C.

Of course they do.

But your observation is still spot on IMO.

DukeLeJeune · #20 03-22-2010, 09:12 PM

Several of my home-audio speakers use an 11-inch woofer, but I just call it a 10-inch. The cone size is similar to a 10", but the frame is a bit larger in diameter. Maybe I should brag that it's about 10% better than a normal 10-inch? Nah, somebody with a 15" woofer will come along and bury me.