Big drivers had their day back in the 60's JBL and Altec Lansing were the 'masters' of 15" bass drivers.
Infinity had its monster bass panel 12" by four or six drivers.. in the 80's
Now the biggest driver is 12" and they are RARE. Most real-life speakers use 10" bass drivers in sets.
The size of the drivers has LITTLE to do with the actual performance!!!
The top-of-the-line, full-range models of most companies still use large drivers (10-12-15 inches). The main playback monitors of any well-funded recording studio--those used to judge the quality of a recording once it's finished--always use large drivers, often two 15-inch drivers in each cabinet just for bass frequencies, and usually horn-loaded mids and highs.
Look at the very expensive models that JBL sells (mostly to Japan) or TAD drivers and monitors, or Westlake or PMC or ATC or the top-of-the-line JM Labs or Tannoy or Zu or Zingali or Klipschorns or Edgarhorns or Pass Labs. There's also Iconic (www.seriousstereo.com), the more expensive Coincident models and many, many others.
It is true that a lot more manufacturers sell slim cabinets with small drivers, but this has more to do with marketing strategy meant to conform with the public's preference for "lifestyle" speakers that fit in nicely with their decor and furniture.
For the lowest distortion and the closest approximation of a live concert atd realistic sound levels, you need high sensitivity and low distortion. There's many good speakers that use small drivers, but no amount of design ingenuity can overcome the laws of physics. What's more, the large cones, heavy cast frames, huge motors and extremely close manufacturing tolerances that high quality larger drivers require are very expensive.
A high quality small driver will of course outperform a low quality big driver, but when cost is no object and dynamics, accuracy and transient response must be as close to "live" as possible, the high-sensitivity 12" and 15" bass driver still rules.
Of course, for small domestic rooms where people listen a low to moderate volumes, quality small-driver systems have their place...and since that's what most people want, that's what's most visible in the market...
Well said - you put it very well. Designers who want uncompromising sound with low distortion at realistic (loud) SPL levels will invariably ALL use larger woofer drivers...although the woofers alone can cost more than many two ways...so it ain't cheap.
Those who are seeking a balance between great sound and to build WAF friendly domestic furniture will invariably choose small woofers in slim designs and these can and do sound extremely good at modest levels but they have, so far, proved unable to compete with their bigger bretheren as almost any studio can attest to.
I also agree that a low cost small woofer is a better choice than a low cost big woofer...if you go big size then it is better to go very high quality ...like the Volts that PMC use. I would also add that a big woofer speaker forces you to go at least three-way which again adds more cost (unless you are prepared to live with some serious degradation from "beaming" when you drive a big woofer into the frequency range where it become directional)
Joe, Shadorne, you are absolutely right. I had posted a short reply and do not know why it did not appear. I simply stated that smaller drivers are not the same as larger in the same way that a four cylinder engine does not perform the same way as a six cylinder engine. It is absolutely wrong to conclude that size of driver has little to do with performance. You are also correct that as one goes higher up in lines of speakers which are considered world class, the drivers almost invariably increase in size, to obtain better results within the laws of physics - as Dr Joe explained.
If I have the space, I never prefer a speaker with smaller drivers, unless I intend to pair it with a subwoofer, but even that is not the same as a speaker designed for full range performance.
If Elizabeth is speaking in terms of tone, then I can agree somewhat. However, there is a definite sense of scale/ease which comes with larger drivers as they move the air more easily. I find that even in the midrange this makes a distinct/very pleasurable difference which to my ear sounds more life-like than what I hear from the majority of more diminutive drivers.
An example of this: I reviewed the B&W CM7 speaker which has a wonderful tonality in the mdirange, but still sounds small due to the 5" midrange. Two other 7" midrange drivers - the 7" Aerogel on the Von Schweikert VR-4 SR MkII, and the 7" mids of the Legacy Focus HD both are much more spacious sounding. A smaller driver simply cannot convey the same spatial clues as the larger ones. However, you are paying much more and taking up more space; it's a game of scale economically and physically.
The Tannoy Glenair uses a huge Dual Concentric driver in which midrange is handled by the big 15" driver. Again, an extension of size, soundstage, etc. which is possible with a larger driver.
Some people honestly are unaware of such distinctions(not trying to suggest you, Elizabeth!), most likely because they have spent little time comparing speakers with radically different driver configuarations. If they go from room to room or store to store hearing a set of speakers each time they will not catch these subtlties that easily, especially if the box components change in each instance. A person then has no clue what the influence of the source/amp/cabling/speaker each is.
In that case, they should either experience the impact of different size drivers through direct comparisons, or if they are physically unable to hear these differences they can pick whatever speaker sounds tonally correct to them and have one less variable to worrry about! :)
After 35 years of playing with this stuff including Apogee,Magnepan,Merlin,B+W,Kef,etc. speakers my Altec Valencia Bs have inspired me to build my own speakers: JBL 2205 15" woofers,Altec 902 drivers on Mantaray horns in a two way configuration.I am as happy with these as anything I have owned!
Limited excursion maters much in audio reproduction small drivers are pushed harder than large they have to work harder to produce same SPL or frequincy range. Large excursions also mask detail that limited xmass drivers reproduce. You see more small for one reason cost. Much cheaper to manufacter design,sell,ship stock small thin speaker systems keep in mind it costs much to ship from china;) and most speaker designs are designed as much for shipping as sound quality, how many fill fit per palet. Plus many manufacters have most in this hobbie thinking small speakers perform better or as well as large. Bose has done much to give this false info much press if you shop for speakers again you will be told 5.1 + cubes is what you need. And now many folks believe its true and that large loudspeakers are dated designs. Sad no wonder so many in this hobbie are gear hounds constantly changing, upgrading. One reason is they keep the small loudspeakers. I will stick with very large loudspeakers with large powerful transducers. For they are the only loudspeaker designs capable of reproducing realistic SPL,image soundstage size and dynamic range.Plus the detail they reproduce and little to no listening fatigue. I can play mine all day long ears never protest unless I push SPL into the crazy range and still loudspeakers hardly working always at ease never hard or forced sounding no mater what SPL I listen too..Sure small has a place many cant afford or dont want a large speaker this I understand but to say small is better is way off the mark. For a monitor I would listen not go by driver size so much unless SPL is very important. A monitor in nearfield is a diferant beast than a floorstander in a main system.
I'm not sure that I buy the argument for larger drivers being presented here. Large drivers can produce high volume levels at low distortion, but they are expensive and require large and more complex enclosures. I don't disagree with that, but the same argument can be used against larger drivers. If high volume and low distortion are the goals then why settle for a 15" driver, or even a pair of 15 inchers? Why not go with a dozen 8" drivers? The 8" array would have slightly less than twice the surface area of a dual 15" design and should be able to go louder with less distortion. Of course, twelve drivers would be more expensive than two and the enclosure would be large and have a low WAF. My point is that it's not the size of the driver, but the overall design they are used in which determines overall sound quality. I guess there is no substitute for total driver surface area.
While an array of smaller drivers can equal the total surface area of a one or two much larger ones and exceed them in efficiency, doesn't the line array introduce it's own problems of sound source localization?
In a tall line array, the distance between the center of the lowest drive and highest is quite far. Wouldn't the ear be able to detect the different points of origination?
Has it all straight.. Facts are facts, bigger the more you can do no doubt..
However I will add the reason for slimmer, smaller cabinets is exactly that. Appeal mostly, and to be fair most small speakers are used because they will perform better in smaller rooms, and smaller enclosures, so if you want Multiple 10 inchers, or a 12 inch, or a 15 inch etc.. You need enclosures the size of most peoples Closets in a house to get optimal performance and make them do what they should be doing.
some subwoofers get past this these days with high excursion and tight cabinets with TONS of power to overcome the need of Huge enclosures, basically Overpower it and it will put out some good bass, or do it the right way and have speakers that take up a whole wall and are very efficient needing less power :-)
Darkmoebius...The line array is the only valid reason to use small drivers. As far as spatial effect is concerned, a line array produces a sound wavefront like a point source far away. The distance to the simulated point source can be varied by curving the line array.
I agree with Onhwy61 about total surface area. In fact, my current speakers have four 8" woofers per side and extend beyond 20 Hz with abundant SPL.
As always, it's more complicated than just size. The drivers have to be designed for bass. If you were to make an array of several midrange drivers they would still be limited, although the SPL within their range would be stunning. The impedance of a typical midrange cone rises at it's lowest limits and an array of them can reach up to 50 ohms @ 50 Hz, depending on how they're wired, etc....
It's possible to have an array of eight 7" drivers that extend no deeper than a single 7", although it'll probably play a lot louder with much less distortion and handle a lot more power.
Darkmoebius: No. It's difficult to explain but well executed line arrays do not have the point source effect due to dispersion patterns, even at nearfield. The concept of pinpoint imaging from a line source is counter-intuitive but entirely possible, actually probable.