In article ,
chris wrote:
Does an aluminium cone harden with the work of moving the air about? Paper
softens. I've seen some old tannoy (guess cira 1960's) ali coned speakers
fetch very high $'s on ebay, so they must still be good.

Yeah, well I saw a Nikon 35mm F/1.4 non-AI lens with a jammed
focussing helicoid and serious cleaning scratches on the front
lens finally for TWICE what a brand new AIS with modern coatings
lists for. I later communicated with the seller, who was
dumbfounded that anyone would in their right mind pay more than
$25 for it, which was my bid.

The fact that some idiot is willing to pay more than good money
for something is NO indication that it's any good. The fact that
an entire group of idots will do the same, well, is merely
depressing.

I've also seen some complex laser stress patterns in the actual cones just
reproducing sine/square/triangular waves, when playing music it gets mega
complex,

Wanna bet? Monsieur Fourier would suggest that this is not the
case.

and the bits of the cones move at different rates and the poor
"rubber" suspension has to cope with the whole lot.
With composite materials it must be worse

Why?

(but according to my ears it
seems to sounds better) but that is probably why the manufactures spend all
that money in R&D.

Actually very little money is specnt, in the grand scheme of
things, on such R&D. I recall, for example, "repeating" some
simply experiments in cone shape and thickness tapering,
experiements that were seemingly obvious, and got a bunch of
interesting results. Interesting in the sense that no one else
had reported them. On talking to a number of engineers at major
driver companies, I was somewhat shocked to learn that NOBODY
had done such experiments, as elementary as they were. Their
"R&D" was to ASSUME such-and-such behavior, and they were, for
the most part, wrong.

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| Dick Pierce |
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