Cone materials

[Guest]

Realistically, which cone materials are best for sound quality? I have always thought that it was paper, having better dampening, low distortion, and a flat response. However, someone has caused me to doubt this. I understand that this is only one of the many variable when considering sound reproduction, but if you had identical drivers, except for the cone materials, which would create better acoustics? This inquiry is not limited to an "the" best material, just wondering which are some (3-5) of the best to consider in a system and why?

[Dirk]

Re: Cone materials

My PERSONAL experience has been that the damping of the cone material seems to be inversely proportional to the driver's resolution. However, corollation is not causation! It may be that the paper and poly cones I've encountered were all cheaper and likely had a higher inductance than those using higher end cone materials. *shrug* Just my personal experience. I've certainly not heard the Revelators, and they're paper.

The big advantage to well-damped cones is that they're much easier to implement in crossover. A few years back, we didn't have nearly the tools we have today, so drivers with ultra-rigid cone materials were a lot harder to work with and get "right". With the prevalence of our computer tools, metal and fibre-composites are well within our capabilities.

[tpremo55]

Re: Cone materials

Nice thread starter - this should be good - I look forward to other's input.

The first question that I would ask would be 'for what?' - are we talking midrange, tweeter, midbass, sub? It *may* matter some.

The second question I would ask is - by what manufacturer? This matters a fair amount too. A ScanSpeak Revelator can't really be held equal to a $10 Pioneer paper cone driver.

The basic desire is to have a cone with the following qualities:
Stiff (to operate in a pistonic fashion)
Light (so the system (driver) can respond quickly to change effortlessly)
Non-resonant (only the facts - no artifacts...)

Aluminum has seen a lot of popularity over the past 6-8 years (maybe longer). It does the things above very well, within the bounds of use. You are likely familiar with the upper level break-up common with aluminum or other metal cone drivers. Titanium falls into this category as well with even a better stiffness to weight ratio.

Paper is the original (I think) material and is still common today. Paper may not have the stiffness that metal does, and may resonate. This has been addressed by doping the cone with various substances, and some other treatments such as slitting on the Scans. You had mentioned how flat the response curves typically are for these - they lack the high end break-up common of the metal cones drivers.

Poly and mineral impregnated Poly is also popular. Poly can flex and is often associated with distortion and/or coloration. However, there are many out there that like the sound of the poly drivers. There have been a number of very well respected drivers in this category from Seas, Vifa, and Peerless. I have a system which uses the Vifa P17(REX) and am very pleased with it.

Ceramic has more recently been introduced with an incredible stiffness and relatively light weight cone. I don't know specifically how it compares to the metal cones in the numbers, but I will say that the systems that I have heard with the Accuton drivers have been excellent.

You will also see wood, bamboo, wool, and others... Some materials are preferred for some applications due to their durability - Car audio applications for instance often use poly drivers.

Each will have their own sonic signatures and will integrate into systems differently. In the end, which one you like and how well it integrates may be your deciding factors.

[Æ]

Re: Cone materials

That question gets asked here once or twice a year.
There is no "best" or "worst" cone material. All the common materials and even exotic materials have been used to fabricate cones/domes. Good and bad examples of all the materials.
Every year some company comes out with a "new" material, designed to impress the uninformed buying public. Lots of hype.
Sound quality is subjective. Whatever you think sounds best. Learn to use your ears/hearing not your eyes. If it sounds good and measures good, great.
However you might be more selective of cone materials when you need certain weather proofing or the ability to stand up to prolonged heat/sun, moisture etc.

Realistically, which cone materials are best for sound quality? I have always thought that it was paper, having better dampening, low distortion, and a flat response. However, someone has caused me to doubt this. I understand that this is only one of the many variable when considering sound reproduction, but if you had identical drivers, except for the cone materials, which would create better acoustics? This inquiry is not limited to an "the" best material, just wondering which are some (3-5) of the best to consider in a system and why?

[Guest]

Re: Cone materials

The first question that I would ask would be 'for what?' - are we talking midrange, tweeter, midbass, sub? It *may* matter some.

I am mainly interested in midrange drivers and subwoofers. For midranges, due to the lack of high end distortion and fairly open crossover points, paper, or paper reinforced cones, seem very reasonable. However, you mentioned several other materials, and I have experienced and seen many others too. These included, poly cones, fibers of various sorts and their integration, such as aramib, glass, carbon, silver graphite, and kevlar, and metals, such as copper, aluminum, and titanium. Would any of these selections, or others not mentioned, pose a clear advantage over paper? In considering this question, due to today's technology, ease of crossing should not play that large of a role, unless the material is extremely finicky.

For subwoofers, the low end distortion from paper is beginning to make it seem like a poor choice. My knowledge of subwoofers is lacking when compared to speakers, but strong fibers or metals would seem like a better choice. Therefore, for subwoofers, which cone materials would accomplish the greatest level of acoustic reproduction?

[Guest]

Re: Cone materials

Thanks AE, that is how I have always selected my drivers. However, the inability to test and listen to the huge selection of materials/drivers lead to this question. For me, paper has always created a very natural, smooth, and flat response, making it one of my favorites. Other materials have been sparking my interest though, and a blatant disapproval from an audiophile of paper, caused me to wonder what else was out there. This post was aimed at simply gaining a better insight of these materials and determining reasonable alternatives for great sound quality other then well designed paper coned drivers.

[brianpowers27]

Re: Cone materials

I suppose one could make some generalizations about each product. I imagine that each product has its own unique distortion/csd character when used in its pistonic range vs above the range. To put it simply, each material density should have its own resonance(s)... There are too many variables to make blanket statements.

I imagine the paper audiophile movement is the by-product of the old way of crossover design. When measurement and notch filter design is clearly within the reach of average DIYers, the game changes.

[curt_c]

Re: Cone materials

I’ll point out that the ‘best’ material may be dependent on an individual’s concept of what his chosen source material should sound like. While demonstratively perhaps not the most resolving material, paper can ‘just sound right’ in many applications, and is a good ‘middle of the road’ choice in many applications.

The other caveat is the source material itself: A well damped (paper, poly, etc) cone, due to their lesser resolution can make marginally recorded material sound tolerable, or even acceptable. Stiff coned drivers of high resolution will let you hear all the imperfections, and in some cases may make a significant part of a music collection intolerable to listen to. –Instead of buying music solely on its musicality, you may find yourself buying only what is recorded well. This applies to the electronics in the equipment chain as well. Those of the 'all amplifiers sound alike' crowd, must have been using well damped drivers for their observations.

Soooo… IMO, the SQ of cone materials is relative to the intended source material. Sometimes when you ‘lift the veil’, you find out why she was covered up in the first place…:eek:

That said, with excellent source material and electronics, a well turned out design utilizing stiff coned drivers will trump more damped drivers every time... -IMHO, of course.

C

[mike1234]

Re: Cone materials

This depends on FR expected and precise formulation/thickness/diameter/weight of the cone. Please don't ask me specifics as I'm not the one to ask.

[Guest]

Re: Cone materials

So, paper, when using high quality audio files, and when using properly crossed frequencies, is not the preferred choice of cone material? If these ideal conditions were obtained, which materials would reproduced these acoustics better then the rest? Again, not limited to "the" best, just the top few which would stand out among the many.

[philiparcario]

Re: Cone materials

I like metal for subs. paper for mids . tweeters ribbons or silk depends on the music. pink floyd is good with ribbions for tweeters. all general the best way to pick material is to listen to drivers. find another diy guy and listen to his stuff. if you are in New Jersey. You are welcome to listen to some of my speakers. i have a few nice speakers with different materials some nice amps. .

[johnnyrichards]

Re: Cone materials

I have always been fond of the sound of Peerless poly cones. I also used to like the old Radio Shack poly cone woofers, more so than their paper coned stuff. The current crop of paper coned (affordable) woofers almost all seem to exhibit breakup or a rising response. I suppose this the tradeoff for a more linear behavior within the passband, but it is increasingly more difficult to find woofers which will run off of a single coil.

I've never DIY'ed a metal coned speaker (not yet, I currently have a project using the Speakercraft 5.25 buyout woofer), but a few years ago I bought a set of aluminum coned Pioneer components for my car. They were horrible compared to the paper cone "old school" MB Quart I replaced them with. I replaced the Pioneer set with the Infinity Perfect 6.1, and they are wonderful. They are the reason I am tackling a metal cone project now.

All in all, listening to carious systems and having built a few over the years I would say I prefer systems with poly woofers and silk tweeters - but that is very likely to be because they are a little more forgiving in a crossover design, with the general lack of breakup nodes.

I am also finding myself listening more and more to the speakers and not the music, how do I break that habit?

[tombrennan]

Re: Cone materials

One can hear good and bad examples of all materials. The drivers that I think make the best upper bass and midrange are paper coned but that doesn't mean their "paperness" is the sole reason they sound good to me or even the main reason.

Note that aluminum has been in constant use as a diaphragm material since the late 1920s. Note too that years ago when JBL started the titanium thing it was because titanium is more reliable than aluminum under high stress, not because it sounds better.

[thenoid]

Go

Realistically, which cone materials are best for sound quality? I have always thought that it was paper, having better dampening, low distortion, and a flat response. However, someone has caused me to doubt this. I understand that this is only one of the many variable when considering sound reproduction, but if you had identical drivers, except for the cone materials, which would create better acoustics? This inquiry is not limited to an "the" best material, just wondering which are some (3-5) of the best to consider in a system and why?

Far more important to "better acoustics" is the implementation of whatever driver you choose to use. Overall driver design. enclosure design, x-over design, listening environment (room acoustics), etc can effect your sound quality much more than cone material...usually speaking. Not to mention that everyone hears and appreciates things differently which makes it extremely difficult to pinpoint a 'best" in most audible situations.

If you are starting out, lurk on the boards here for a while, keep asking good questions, take a few proven designs and build them. Once you feel comfy enough, jump in a design your own with your own goals in mind and YOU tell us what material sounds best in your design and why. That's the fun in it all...

Noidster
________
CherryMarry live

[curt_c]

Re: Cone materials

A couple of thoughts:

If we assume the ideal driver would faithfully convert the electrical stimulus received to its acoustic counterpart, one could make the case that the ideal cone material would exhibit purely pistonic behavior throughout its intended excursion and frequency passband. This would suggest that the ideal cone material it would be infinitely stiff. –So why do some paper and loaded poly cones sound so good?

Aside:
I think for many the tendency is to consider distortion as a simple factor or factors. -In truth distortion is a complex entity, dependent on many factors which vary with the frequency content of the source material and the drive level of that signal. Differences in motor design will not only change IMD and THD, but in the case of THD, the spectra the distortion it is comprised of, leading (IMO) to audible differences in sound between otherwise similar drivers.

IMO, much of the ‘sound’ of a given driver is not solely due to cone material, but also the motor design and how well it is executed. It’s the synergy of the system that makes a poor or excellent driver. At least some of the ‘character’ of our favorite drivers is due to their attendant distortion spectra. Consequently, (at least for me) it’s often difficult to separate out a single aspect of a driver design and make practical observations based on subjective experiences.

Back on topic:
A damped cone will absorb some of this low level distortion. It doesn’t get converted to acoustic energy, and its audibility is diminished or eliminated. This distortion could be generated by the driver, but also by the source material or electronics in the chain. –The actual distortion source doesn’t matter, as you won’t hear it. This is a ‘good’ thing as far as it goes.

What does matter is the low level signals on the source material that are equal in level to or lower than the distortion that was just absorbed. This will probably include some of the ambience and spatial clues captured during the recording, as well as other fine detail. -Those signals that likely provide the sonic realism to the recording are also absorbed or attenuated and you won’t hear them. This is definitely 'not' a good thing…

OTOH, an undamped stiff cone will pass all the low level detail AND the distortion along into the acoustic realm. All the warts and blemishes from the source material and electronics chain are audible as well as those ambience and spatial clues. Is this the fault of the driver? Personally I don’t see noise reduction as being a necessary part of the driver’s function. -Those issues are better resolved elsewhere.

C