Thanks. Yes, the thing I read -although KEF always claimed consistency of plastic was their unique quality- the opposite was quite true for Bextrene and Polypropylene: the risks were substantial two batches were not quite alike.
What do you mean by "cone felting"?
What do you mean by "cone felting"?
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In principle I like using a notch filter on a woofer with a single well behaved peak, but the deeper the notch, the more it will get messed up by batch differences.
I have first hand knowledge of KEF, Celestion & Wharfedale consistency but you'll forgive me if I don't provide details. I still need good friends there if I ever abandon the beach. The most consistent drive units ever were/are certain 'polyprop' units.
I had a big hand in this; one of my proudest and most satisfying achievements.
Paper is made by a 'felting' process. From Wikipedia
"In papermaking, a dilute suspension consisting mostly of separate cellulose fibres in water is drained through a sieve-like screen, so that a mat of randomly interwoven fibres is laid down. Water is further removed from this sheet by pressing, sometimes aided by suction or vacuum, or heating."
Speaker cones are still made by this very traditional method.
Gotta point out that though I was instrumental in developing Engineered Plastics for cones, paper (or what called Unique Fibrous Material 😊) is NOT inferior; certainly above about 90dB/W.
The breakup pattern is different for a good sounding paper cone compared to a good sounding 'plastic' cone but they have a similar controlled shrinking 'piston' area with frequency.
The only con is that the consistency of the best paper cones isn't as good as that of the best 'plastic' cones.
Thanks: I am familiar with the production of paper, but I never heard the term "paper felting" before, hence my asking. I am aware of the pro's and con's of various cone materials and the various issues that come along with each of those. Vaccuum forming of cones from sheet plastics looks like a god sent cone production method: never before was mass production of cones so cheap and easy. From what I have seen, forming of Kevlar and glass fibre is not much different, but I may be mistaken here.
Did you ever experiment with bio-cellulose materials?
Not sure what you mean. Paper is sorta bio-cellulose.
OK. I've looked up bio-cellulose in Wikipedia and it seems to refer to very fine fibres. But what's the advantage? The opposite direction from Kevlar, GF and other 'woven' materials which I don't like either.
If you look at the back of some of the 'softer' KM cones, you'll see why I refer to it as 'felting' 😊
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Well pulp is a biological material, made from plants.
If you want better consistency you need to source it all from one place.
Again Pioneer /TAD did that by buying they're own pulp plantations to keep the raw material and process as consistent as possible.
If you want better consistency you need to source it all from one place.
Again Pioneer /TAD did that by buying they're own pulp plantations to keep the raw material and process as consistent as possible.
I should have added bacterial... My bad.
2. Dome speaker, Matusiak G. et all; Rights: Institute of Biopolymers and Chemical Fibres, Tonsil S.A. Września. Protected by patent number: 204309. Polish Republic Patent Office, BUP 08-04-2002, no. 08/2002. The shell vibration and sound radiation were studied. Diaphragm speaker of bacterial cellulose the so-called bio-cellulose, as well as a complete speaker composed of the membranes were designed and patented.
2. Dome speaker, Matusiak G. et all; Rights: Institute of Biopolymers and Chemical Fibres, Tonsil S.A. Września. Protected by patent number: 204309. Polish Republic Patent Office, BUP 08-04-2002, no. 08/2002. The shell vibration and sound radiation were studied. Diaphragm speaker of bacterial cellulose the so-called bio-cellulose, as well as a complete speaker composed of the membranes were designed and patented.
That's rubbish! The most important factor (apart from being hand carved from Unobtainium & solid BS by virgins) is the water.
Sony used pure water from Mount Fuji.
We (and KM, UK) used water from Esholt Sewage Works for our UFM (Unique Fibrous Materal) cones. 😊
You should not forget to mention that plant was run by barefoot women from the Eastern Esholt Isles. That is what did the trick, not the water as such.
Actually not. Consistency in raw material generally always makes a more consistent end result. Keeping to a single supplier, same soil, same species ensures consistency of the raw material.
Sorry if you do not like it.
Yes, so painful to watch how woofer engineers are enjoying themselves while little users like myself are suffering from cone breakups... alone, in the snow...
Suffering is the truth, I prefer silence over listening to most speakers, even many of those with supposedly well-controlled cone behavior (with glaringly obvious resonances on the SPL chart).
That said I have no idea how much effort is required to make a better one, and to be successful in the market at the same time, so I think any sense of entitlement would be misplaced. It's just that when I see that people can improve speakers just by sticking things on the cone, it's obvious that there is a lot of wasted potential and we evidently cannot rely on manufacturers to go past a certain point if they are not selling to high-rollers.
That said I have no idea how much effort is required to make a better one, and to be successful in the market at the same time, so I think any sense of entitlement would be misplaced. It's just that when I see that people can improve speakers just by sticking things on the cone, it's obvious that there is a lot of wasted potential and we evidently cannot rely on manufacturers to go past a certain point if they are not selling to high-rollers.
Actually some very successful manufacturers probably consider ugly cone breakup a positive feature, when the "average home user" likely did not toe-in or sit in any sweet spot. Mark Audio drivers' monster plateau became flat-to-15khz off-axis 30-45° (MA200 tested); surely intentional, as Mark Fenlon had studied with Ted Jordan.
I don't know how long miracle automotive heat-resistant tape "plast" has been around....
I don't know how long miracle automotive heat-resistant tape "plast" has been around....
I hope some day mine will look and sound as good as yours.
My minimalist XO-less "LXmidi" uses 8" and 4" fiberglass-honeycomb drivers of the same make (cone material and FR similar to Mivoc XAW-208-HC/XAW-110-HC), using off-axis attenuation as low-pass and open-baffle fall-off as high-pass; I could not hear "two" drivers. Inside the can is a folded concentric transmission line which the 8" loves. The 4" later got treated to a "plast & whizzer" that nulled the HF cone breakup and extended very HF to go tweeterless.
My minimalist XO-less "LXmidi" uses 8" and 4" fiberglass-honeycomb drivers of the same make (cone material and FR similar to Mivoc XAW-208-HC/XAW-110-HC), using off-axis attenuation as low-pass and open-baffle fall-off as high-pass; I could not hear "two" drivers. Inside the can is a folded concentric transmission line which the 8" loves. The 4" later got treated to a "plast & whizzer" that nulled the HF cone breakup and extended very HF to go tweeterless.
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Nobody disputes consistency: it is about the plantation. IKEA and SAPPI e.a. own plantations. Pioneer/TAD does not. Period.
So what happens to a paper cone as you start adding ribs? How do you know when to stop? How do you know where the ribs are needed?
Buy or build a laser interferometer and start to explore. That stuff is readily available these days, unlike (almost) 50 years ago…
After seeing this discussed multiple times over the years, I get the impression no one who actually knows about it, actually wants to talk about it. It's either that, or no one who actually knows about it, actually knows about it...
I'm inclined to believe that some published studies could have been done better, especially given what is known today about perceptual testing. Also, a lot of published DBT results seem to be taken as too literally exact by engineers who are used very accurate and precise measurements made in the hard sciences.
@kgrlee, if your reason for not commenting now is because you no longer have a horse in this race, what did you comment on regarding DBT when you did have a horse in the race? Anything?
In dem days, I represented a major speaker maker so it would have been inappropriate for me to mouth off.
These days, I'm a professional beach bum so can say what I like. I'd be happy to comment on da false prophets except I no longer have access to their august scribblings. Even as a beach bum, I don't want to rant in detail about something I only dimly remember from 25+ yrs ago.
It should be obvious that I do a lot of sh*t stirring these days but I try not to say anything that's actually wrong except when it should be blatantly obvious 😊
Of course if some kind soul is happy to send me copies of their prodigious output, I might tear myself away from da Great Barrier Reef and produce an academic critique ... but don't hold your breathe.
I might describe bits of how I think a DBLT should be conducted but it would take a book or two for da full Monty.
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