Why did Bextrene drivers disappear?

[gearhound]

Hello audio fanatics!!
I have a pair of B&W DM12 speakers at home, that I bought new in 1981.
Each speaker has a 6" Bextrene mid/woofer and a 1" textile dome tweeter.
VERY smooth sounding speaker!!
I've build a few DIY speakers over the last 20 years.
But whether it's Madisound, Parts Express, etc......I don't EVER recall seeing Bextrene drivers as an option!?
Was it the cost of manufacturing that drove Bextrene drivers from the market?
Or did the audio guru's decide that OTHER cone materials were superior?

Steve :scratch2:

 

[soundmotor]

I've build a few DIY speakers over the last 20 years.
But whether it's Madisound, Parts Express, etc......I don't EVER recall seeing Bextrene drivers as an option!?
Was it the cost of manufacturing that drove Bextrene drivers from the market?
Or did the audio guru's decide that OTHER cone materials were superior?

Steve :scratch2:

IIRC, bextrene was the name a certain plastic was known as in the UK so that is likely why many companies from there used it/talked about it.

 

[soundmotor]

It is basically a man-made fiber, although it is really made from wood.

Bextrene is polystyrene but I don't believe it comes from wood.

 

[soundmotor]

Nope - it is regenerated cellulose acetate (basically like Rayon). That is what the quote I put up says anyways.

Dave

Everything I can find is that polystyrene (Bextrene) comes from petrochemical sources.

Polystyrene

Bextrene appears to be the unique trade name for polystyrene not for a unique plastic type. The owner of that trade name was Bakelite Xylonite Ltd. In the early 70's they were sold off to BP Chemicals & perhaps that change in company direction eventually eliminated the material from cost effective use by UK speaker manufacturers?

I can think of a couple similar events. One is that Kapton is now not generally used in the loudspeaker industry. Polyimide is still available from other suppliers globally but DuPont's branded Kapton became too expensive. The other was the plastic dome material ADS used for its later tweeters called Carlona (IIRC?) by Shell Oil. The price shot way up and they had to find a substitute. I would suspect that economics more than anything else led to Bextrene's decline.