Okay,
I've got another question for you guys. Recently my friend got some carbon-fiber woofers, expecting them to be the end all of acurate bass reproduction. I asked him why, dispite his engineering backround, about the best he could give me was "because they're carbon fiber man... CARBON FIBER".
These days I begin to wonder wether expensive drivers are really worth the money (you get a performance increase that justifies the cost) or if you are buying massive placebos.... at any rate thats not the point of this post.
My question is this-
What effect does the cone material have on sound?
The varieties I have run into:
Paper
Aluminum
Poly
Nickel
Carbon Fiber
Woven Glass Fiber
Mica filled variations of the above.
What differences do these materials make and what are the realistic differences, and are they worth paying more money for.
And it has been explained to me what the differnece in tweeter materials make (alum vs. soft), so this question is in regards to woofers...
I would like to think I could judge drivers by thier freq.response graphs, but people seem to make a big deal over thier materials....
Thanks In Advance Guys,
Victor
I've got another question for you guys. Recently my friend got some carbon-fiber woofers, expecting them to be the end all of acurate bass reproduction. I asked him why, dispite his engineering backround, about the best he could give me was "because they're carbon fiber man... CARBON FIBER".
These days I begin to wonder wether expensive drivers are really worth the money (you get a performance increase that justifies the cost) or if you are buying massive placebos.... at any rate thats not the point of this post.
My question is this-
What effect does the cone material have on sound?
The varieties I have run into:
Paper
Aluminum
Poly
Nickel
Carbon Fiber
Woven Glass Fiber
Mica filled variations of the above.
What differences do these materials make and what are the realistic differences, and are they worth paying more money for.
And it has been explained to me what the differnece in tweeter materials make (alum vs. soft), so this question is in regards to woofers...
I would like to think I could judge drivers by thier freq.response graphs, but people seem to make a big deal over thier materials....
Thanks In Advance Guys,
Victor
Addition
Oh and paper/wool material in drivers too....
like those in the silver flute woofers.
Thnx
Victor
Oh and paper/wool material in drivers too....
like those in the silver flute woofers.
Thnx
Victor
The best drivers tend to be expensive. But there's lots of expensive drivers that aren't so wonderful. Cone material, geometry, and termination all interact to give a driver a characteristic "sound." Stiff cones tend to be more pistonic in their operating range, but break up more suddenly. Cones made from low loss materials can have extended bandwidths, but suffer from reflection colorations from their surrounds. Lightweight cones can be efficient, but can also let a lot of box noise and reflections pass through them. And so on and so on.
"They're carbon fiber, man." Priceless. This one goes to 11.
"They're carbon fiber, man." Priceless. This one goes to 11.
It is my observation that cone material and shape make the biggest difference, and is the most difficult part of loudspeaker driver design.
Pretty much anyone can get a decent magnet, frame and voice coil without much effort off the shelf. Much of what distinguishes the best drivers from the crap is purely the diaphragm surface.
In the old days, cone quality was achieved through black arts, sweat, and listening. These days the lesser designers want to pretend that the cone is a rigid piston. This certainly makes for easy analysis, but rarely results in the best sound.
Personally, I am amazed that we have made so little progress.
Regarding carbon fiber, Audax makes a really sweet carbon fiber 8" driver good up to about 2 KHz, but wouldn't you know, all the other versions of this cone from them are not nearly as good.
Pretty much anyone can get a decent magnet, frame and voice coil without much effort off the shelf. Much of what distinguishes the best drivers from the crap is purely the diaphragm surface.
In the old days, cone quality was achieved through black arts, sweat, and listening. These days the lesser designers want to pretend that the cone is a rigid piston. This certainly makes for easy analysis, but rarely results in the best sound.
Personally, I am amazed that we have made so little progress.
Regarding carbon fiber, Audax makes a really sweet carbon fiber 8" driver good up to about 2 KHz, but wouldn't you know, all the other versions of this cone from them are not nearly as good.
There are a couple of very good papers by Lynn Olsen regards driver construction titled " Looking Over My Shoulder Part 1 & 2": Do a search, it is a very interesting topic.
The arguments are for good self damping, rigidity and low mass. While the cone profile tends to effect rigidity (straight cone), it is also used to control cone breakup (curved cone).
Despite the hype, my worst listening experience is with Kevlar woofers, they tend so sound brittle and dry, and when pushed suffer from "bad cone cry".
Paper, and paper blends tend to have the least problems and are easier to work with for crossover design (for diy), but there are exceptions.
They also tend to sound the most natural, know wonder so many old paper cone drivers sound to good.
Heres a good contemporary paper cone design I spotted for sale recently (it also uses horn loading for other reasons). This is the third re incarnation of a paper driver design spanning 30 years courtesy of JBL.
Mr Pass has surveyed quite a few drivers in the development of the excellent active Passlabs Rushmore Loudspeaker, with the exception of the high frequency driver, is appears to be a paper cone based system.
Here is another very informative article by Mr Pass:
http://www.passlabs.com/pdf/rushmore.pdf
Time for a glass of Cab Sav.
macka
😉
The arguments are for good self damping, rigidity and low mass. While the cone profile tends to effect rigidity (straight cone), it is also used to control cone breakup (curved cone).
Despite the hype, my worst listening experience is with Kevlar woofers, they tend so sound brittle and dry, and when pushed suffer from "bad cone cry".
Paper, and paper blends tend to have the least problems and are easier to work with for crossover design (for diy), but there are exceptions.
They also tend to sound the most natural, know wonder so many old paper cone drivers sound to good.
Heres a good contemporary paper cone design I spotted for sale recently (it also uses horn loading for other reasons). This is the third re incarnation of a paper driver design spanning 30 years courtesy of JBL.
Mr Pass has surveyed quite a few drivers in the development of the excellent active Passlabs Rushmore Loudspeaker, with the exception of the high frequency driver, is appears to be a paper cone based system.
Here is another very informative article by Mr Pass:
http://www.passlabs.com/pdf/rushmore.pdf
Time for a glass of Cab Sav.
macka
😉
Attachments
Different sounds with the same material
You can't even generalize about the sound of cones of a certain material or shape.
Take aluminium cones with the same size and shape. There are differences in sound depending on:
Purity of material
Thickness of material
Hardness of material
Surface treatment - is it anodized? What type of anodizing?
Coating
Also the consistency of any of the above affects the sound. Is there more thickness/hardness/whatever in the center of the cone than on the outer edge?
Steve
You can't even generalize about the sound of cones of a certain material or shape.
Take aluminium cones with the same size and shape. There are differences in sound depending on:
Purity of material
Thickness of material
Hardness of material
Surface treatment - is it anodized? What type of anodizing?
Coating
Also the consistency of any of the above affects the sound. Is there more thickness/hardness/whatever in the center of the cone than on the outer edge?
Steve
thanks for all the replys, you're right, this is a little out of toppic for pass, I thought I was posting in Loudspeakers, will move.
Thanks again.
Thanks again.
alrighty this has been moved for me, THANKS!
Well I guess I need to know this, what are the "ideals" or what are people "trying" to achieve when they use each of these materials?
Thanks Brian
Well I guess I need to know this, what are the "ideals" or what are people "trying" to achieve when they use each of these materials?
Thanks Brian
This is a particularly interesting topic for me, as it is one of
the areas where simulation and analysis has been less
successful than hard work and good taste.
I like to work with speakers, and in spite of the fact that none
have previously surfaced publicly, I've been doing it for about
35 years, well before my time at ESS.
Most of it comes down to driver quality, and most of the process
of selecting drivers comes down to begging, borrowing, stealing
and even buying every driver you can and seeing what they are
like. Unless they are obvious dogs, it's important to spend
serious time teasing the best out of each one. A good electronic
crossover, measuring equipment, lots of complementary drivers,
lots of time and a good pair of ears is essential.
The best part is that you develop good ears with the practice,
you don't have to start out with them.
😎
the areas where simulation and analysis has been less
successful than hard work and good taste.
I like to work with speakers, and in spite of the fact that none
have previously surfaced publicly, I've been doing it for about
35 years, well before my time at ESS.
Most of it comes down to driver quality, and most of the process
of selecting drivers comes down to begging, borrowing, stealing
and even buying every driver you can and seeing what they are
like. Unless they are obvious dogs, it's important to spend
serious time teasing the best out of each one. A good electronic
crossover, measuring equipment, lots of complementary drivers,
lots of time and a good pair of ears is essential.
The best part is that you develop good ears with the practice,
you don't have to start out with them.
😎
What's needed is a material that's infinitely rigid, but also infinitely damped. And if you know of one, let us know😉
Different cone materials have different degrees of this, and then there are all the practical manufacturing limitations, etc.
Of course, what you want to know is how they sound. Well, this isn't really an easy answer because there are way too many variations. There are many types of poly, paper, carbon fiber, metal, kevlar, wood pulp. What there isn't is a clear set of objective tests that can measure and correlate exactly with what you hear.
Sure, you can do frequency response, linear and nonlinear distortion. Does this explain everything you hear? Not fully, though objective tests are useful.
There are good examples of many different materials. Getting a sample of each and working with them to get the best sound is really the only way to do this.
Build something with an excel, an eton, a scan paper, etc and see.
Different cone materials have different degrees of this, and then there are all the practical manufacturing limitations, etc.
Of course, what you want to know is how they sound. Well, this isn't really an easy answer because there are way too many variations. There are many types of poly, paper, carbon fiber, metal, kevlar, wood pulp. What there isn't is a clear set of objective tests that can measure and correlate exactly with what you hear.
Sure, you can do frequency response, linear and nonlinear distortion. Does this explain everything you hear? Not fully, though objective tests are useful.
There are good examples of many different materials. Getting a sample of each and working with them to get the best sound is really the only way to do this.
Build something with an excel, an eton, a scan paper, etc and see.
Thanks Again, now more answers
Okay, for examples sake, lets take one of my current projects. I am considering useing one of the two listed below tang band drivers. They will be used in MMTMM confing with a Ribbon that can pick up at 2K, but prob shoudlnt pick up untill 3k. The odd thing is they have about the same specs but different materials. So the question is...
do we like Aluminum
or Paper? http://www.partsexpress.com/pdf/264-818.pdf
Right now I am leaning torwards the aluminum because all else seems equal and aluminum looks shinny.... But that should not be the reason I end up picking a driver, so help a wantabe audiophle pick drivers with some reason besides looks!
Thanks
Okay, for examples sake, lets take one of my current projects. I am considering useing one of the two listed below tang band drivers. They will be used in MMTMM confing with a Ribbon that can pick up at 2K, but prob shoudlnt pick up untill 3k. The odd thing is they have about the same specs but different materials. So the question is...
do we like Aluminum
or Paper? http://www.partsexpress.com/pdf/264-818.pdf
Right now I am leaning torwards the aluminum because all else seems equal and aluminum looks shinny.... But that should not be the reason I end up picking a driver, so help a wantabe audiophle pick drivers with some reason besides looks!
Thanks
That depends on the application and the implementation. We often take it as a given that rigid and pistonic is best, and it often is. But not always.
A friend lent me a home made aluminium driver some time ago and it worked superbly. The cone was spun on a lathe and had similar feature to the one you referred to.
A deep understanding of the electro mechanical aspects of driver design is required to ge the end result, and of course the application. I think this is where Steve was coming from.
Assuming the driver is properly desiged the thing is to make sure you only operate on the pistion range.
macka
A deep understanding of the electro mechanical aspects of driver design is required to ge the end result, and of course the application. I think this is where Steve was coming from.
Assuming the driver is properly desiged the thing is to make sure you only operate on the pistion range.
macka
Hey listen, I don't design drive units. I just try to design enclosures so that they don't screw up the drive units that I select. So I'm not putting myself forward as an expert in this area. Hopefully, those with more expertise will come forward and enable us all to learn a little more.macka said:
But I'm not sure if the statement above is correct, macka.
As Sy said:
In theory, the first resonance or breakup frequency of a small diameter tweeter may be above the range of audibility, if the tweeter is small enough. In practice, I think that real tweeters, dome or cone, breakup at a much lower frequency. This is partly due to irregularities in the material but also due to the behaviour of other parts of the driver such as the surround, the mass of the coil (which becomes significant at higher frequencies) and the spider (where one exists).
If this is true, and I'm sure that someone will jump in here if it's not, then the issue becomes one of having the drive unit break up in the least unpleasant manner possible. This is the domain in which, I believe, coatings such as C37 can play such an important part (see the current thread: "Stuff to paint on speaker cones").
In any case, true or not, many people (myself included) prefer their music to be played through full-range drivers than through a mid/bass unit handing over to tweeter of a different character with (presumably) better high frequency characteristics. Now, we know that, even in theory, there ain't a full-ranger out there that doesn't have its breakup modes well within the audible range. Therefore, how bad can breakup be, provided it's well handled?
I believe that I'm a little out of my depth here but I'm learning as I go. One thing I know for sure and that is that Nelson Pass is 100% on the money when he says:
In other words, we've got to listen.
I would only add that the more that we can also listen to live music, the more we'll know what we're listening to.
Steve
Steve,
I did not mean to complicate things here,
This topic is like a wishing well, the deeper you look the more you see.
What is was elluding to was the unpleasantness you referred to. Obviously , if the driver can be run over the range where it in fact operates as a piston, then maximum accuracy will be the outcome.
However, for the pruposes of the wider system design, we can bend the rules, stretch the envelop and manage the breakup mode to be more pleasant if that is whats required.
There a some good examples of this using various techniques
ie the JBL LE8T and at the other extreme the Bandors
In fact, I use titanium compression drivers which are dated, the newer versions have a coating called aquaplas to moderate these resonances.
best regards
macka
I did not mean to complicate things here,
This topic is like a wishing well, the deeper you look the more you see.
What is was elluding to was the unpleasantness you referred to. Obviously , if the driver can be run over the range where it in fact operates as a piston, then maximum accuracy will be the outcome.
However, for the pruposes of the wider system design, we can bend the rules, stretch the envelop and manage the breakup mode to be more pleasant if that is whats required.
There a some good examples of this using various techniques
ie the JBL LE8T and at the other extreme the Bandors
In fact, I use titanium compression drivers which are dated, the newer versions have a coating called aquaplas to moderate these resonances.
best regards
macka
Only in the nearfield. For the farfield (where people listen), that is often not the case. Some well-designed breakup modes can help dispersion, driver integration, and crossover smoothness if taken into account in driver and system design. Go measure that cheap Tonegen 4 incher that NHT uses in the Super Zero with no lowpass crossover. That's a darn nice piece of design work.
I've heard good and lousy speakers with rigid cones. I've heard good and lousy speakers with ripply, flexy cones.
Steve,
You appear to be running around the hedge maze a little...
Two enter man enter...one man leave Said Jackie Chan (a joke)
My expierence is the pro recording area where generally we listen in the near field, or in larger enviroments the mid field.
That said, as you move further to the rear of the room, the ear picks up more reverbant & reflected sound, think of it as a less deliberate version of the Bose idea.
Generally, when I go to the concert hall, I like to sit in the middle next to a gorgous woman. I find both very complimentary.
The rear is best left for those who fart and snore a lot....Muhahahah
macka
You appear to be running around the hedge maze a little...
Two enter man enter...one man leave Said Jackie Chan (a joke)
My expierence is the pro recording area where generally we listen in the near field, or in larger enviroments the mid field.
That said, as you move further to the rear of the room, the ear picks up more reverbant & reflected sound, think of it as a less deliberate version of the Bose idea.
Generally, when I go to the concert hall, I like to sit in the middle next to a gorgous woman. I find both very complimentary.
The rear is best left for those who fart and snore a lot....Muhahahah
macka
Without having heard either, it comes down to specs. While the paper doesn't have as flat a response, it's much better damped, has a lower Qes, and depending on its polar response and wave speed through the diaphragm, you may be able to run them high enough to take sufficient load off the ribbon and get the XO out of our acute hearing BW.
On specs alone, it's a no-brainer for me, especially since I prefer paper in most cases, don't want any more components in the signal chain than absolutely necessary, and don't like the gross tonal mismatch of a ribbon and point source driver. 😉
GM
On specs alone, it's a no-brainer for me, especially since I prefer paper in most cases, don't want any more components in the signal chain than absolutely necessary, and don't like the gross tonal mismatch of a ribbon and point source driver. 😉
GM
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