Speaker Cones: What are the differences?

[roshi]

So I've been looking at hundreds of different speakers, all with different type of cones, made out of different materials. There are the paper cones, the ones out of different metals or even Kevlar. Now people always bash bose for using paper cones, but many other companies (including ones people like) use paper cones too.
So what is really the deal between the different materials?
Thanks!

 

[Joe Schmoe]

Manufacturers would like you to believe that their cone material is somehow "special", but it never is. The overall design and build quality are far more important. A given material can be used well or poorly. Bose are junk because they are badly designed and badly made, not because they use paper.

 

[no. 5]

Now people always bash bose for using paper cones, but many other companies (including ones people like) use paper cones too.

Think about what drivers the other company's used paper in.

B&W, for example, uses treated paper in some of there subwoofers, Bose uses a two inch non treated paper cone to reproduce mid and high frequency's; so it is in effect, a two inch paper cone tweeter. Which is a poor choice for a tweeter.
That is, in addition to the other deficiencies of the design.

 

[annunaki]

Certain materials work better for certain applications. Lat's take B&W for example.

For tweeters they use Aluminum and Diamond (in the high end designs). These materials work very well because of their pistonic behavior and high break up frequency (above 40Khz an higher for the Diamond domes) above the audible range.

For midrange divers they almost exclusively use Kevlar. Kevlar works well in dissipating back wave reverberations and is excelent in keeping resonances out of the operating frequency bandwidth (damping characteristics).

For Bass divers they tend to use Aluminum and a treated paper kevlar mixture. These cones tend to be very stiff relatively lightweight and have little to no resonances in the operating bandwidth.

Obviously none of that matters if the motor design voice coil and suspension design are not all taken into account as well. The cone is one part of system of parts on each diver. Just as the driver is one part of a system of parts in the entire speaker. The sum of the parts working together and integrating properly s what will determine a good end result.

The enclosure can have a bigger effect than the drivers in many cases if resonance issues are not properly addressed. Many mainstream speakers suffer a fair amount of resonance issues yet many are not looked into because many people are so used to hearing them. Not to mention caninet design and parts would make some of the speakers very expensive.

Good speaker designers realize this and that is why so much attention to detail is made on each individual aspect of the entire working system.

 

[fmw]

I would go even further and say that the enclosure is always more important than the drivers.

 

[cornelius]

Think about what drivers the other company's used paper in.

B&W, for example, uses treated paper in some of there subwoofers, Bose uses a two inch non treated paper cone to reproduce mid and high frequency's; so it is in effect, a two inch paper cone tweeter. Which is a poor choice for a tweeter.
That is, in addition to the other deficiencies of the design.

Ah, but my Sequerra monitors have a paper cone tweeter, and are excellent speakers. As others have said here, it's in the (whole) design. The materials in my Ohm Walsh speakers are not esoteric by any means, but the designers implemented these materials in such a way that the sonic results far exceeded what one would expect.

 

[Swerd]

There are a number of different speaker cone materials: polypropylene, paper, glass, carbon and kevlar fiber, aluminum, and magnesium. And there is significant debate over whether the differences among them is audible. I have listened to enough poly, paper, and metal drivers to believe that I can hear differences among at least some of them. The reasons why they might sound different are widely discussed, but these discussions are usually broad generalizations. If any general rule does exist to explain why speakers with different cone materials sound different, there are sure to be many exceptions to it.

I know of one paper that begins to explore this question. It is a white paper written by Floyd Toole of Infinity. Yes, it has an obvious commercial interest to it, but Toole has an excellent reputation, and his work lays the foundation to why different cone materials may sound different.

Ceramic Metal Matrix Diaphragms
A Technical Report On Ceramic Metal Matrix Diaphragms
By Floyd E.Toole and Allan Devantier
http://www.infinitysystems.com/home/technology/whitepapers/cmmd.pdf

 

[no. 5]

Ah, but my Sequerra monitors have a paper cone tweeter, and are excellent speakers.

I was unaware of the existence of high-quality paper cone tweeters.

Bet they cost more than the paper cone wizzers I was referring too.

 

[cornelius]

Yeah, these Sequerras are the only speakers that I've heard with a paper cone tweeter that I ever liked. They're not terribly expensive speakers, and I think **** Sequerra builds the tweeters himself, not totally sure...they sound great!
Bose on the other hand...