Interesting Conversation

[mah]

During my visit to Lorantz Audio Services, the sole Australian loudspeaker driver manufacturer and similar in operation to GPA, I asked the owner if he had any light weight, rigid, 15 in. speaker cones. Well, he opened up and we could have had a good session on the topic. He had good things to say about the Altec 515.

Unfortunately I had an appointment elsewhere. He did say that he would like to recreate some cones from his days at the Rola organisation. Not possible. Current cone making fibres are not as stiff as the originals and the bonding agents currently used are water based and a give surface bond on the fibres rather than a penetrating bond that the original resins achieved.

The result is a heavier cone to achieve a comparable stiffness. Forest depletion and environmental regs. regarding emissions combine to thwart the time machine - at least in Oz.

Food for thought, Marshall.

[Ronald Lee]

Wow, you guys in the "land down under" are also afflicted with this environment political correctness stuff also. Petroleum solvent based paints and probably glues were banned sometime ago, in California, and the rest of the US. The problem that I see is that for example paints, the chemists haven't developed anything comparable to the old petroleum based products, ie in terms of durability and hardness.

The speculation that part of the reason for the Columbia Space Shuttle disaster was the switching of the glue holding on the heat shielding tiles on the shuttle nose to a more "environmentally friendly" glue. In the past those clunks of ice hitting the tiles wouldn't have been a problem, but with the more environmental friendly glues this was a different story.

It is going to take time and money to develop comparable performance of older products using newer manufacturing techniques and materials.

[Audio_by_Goodwill]

Petroleum solvent based paints and probably glues were banned sometime ago, in California, and the rest of the US.

No, not the rest of the US, only parts. It's become more limited recently....... I think only quarts are available now in some products rather than gallons. I'm speaking of paint...... I have no exposure to most/many glues.