[spacemanspliff]

I have done a bit of looking around but can't find a specific definition as to what the Stax drivers are made of and how they are lighter than air?

 

[Duggeh]

The diaphragms are made of a special kind of plastic under high tension and aren't lighter than air. The rest of the driver assembly is made of a combination of metal and/or plastic or PCB or both depending on the model.

Materials that can be used in an electrostatic driver aren't limited to what Stax has used throughout its design history. The HE90 for example, uses glass in the assembly.

 

[i_don't_know]

It's just three electrons/whatever/one of those particle things squashed between three super thin sheets of some material, right?

 

[mypasswordis]

Not really. There is a thin mylar diaphragm, then thin spacers between the diaphragm and the two metal stators. Where did you read they were lighter than air?

 

[spacemanspliff]

I read it in a Stax review.

Just had someone(Nicolaskl) on hardforums figure it out however. It means that the drivers are lighter than the pressurized air (sound waves) which it displaces. So the drivers are lighter than pressurized or concentrated air.

 

[sunseeker888]

PCB? Unlikely if you mean polychlorinated biphenyls......

 

[b0dhi]

Its only a matter of time before someone makes an electrostat with a carbon nanotube sheet diaphragm. That'd be somethin. YouTube - carbon nanotube speaker

 

[Duggeh]

Quote:

Originally Posted by sunseeker888 /img/forum/go_quote.gif PCB? Unlikely if you mean polychlorinated biphenyls......

I should have said PCB material. The stuff thats non conductive that forms the base for a printed circuit board.

 

[krmathis]

They are not!

They weigh more than air, but a whole lot less than dynamic headphone drivers...

 

[AzN1337c0d3r]

Quote:

Originally Posted by Duggeh /img/forum/go_quote.gif I should have said PCB material. The stuff thats non conductive that forms the base for a printed circuit board.

Just FYI, Printed Circuit Boards are usually composites composed of either cotton paper or glass and epoxy resin. Furthermore they are usually laminated with PTFE (aka teflon).

OP: There aren't really any solids which have less density than air. Even Aerogel, one of the least dense solid known to man, is denser than air (that and it being 99.8% air to begin with). Anything that is less dense than air would simply float away out of the atmosphere. There would be a major challenge manufacturing it.

 

[phkd]

they technically can be lighter than air... if you define the amount of air properly. But as the poster above me said it, they certainly are less dense than air, making them heavier than an equal volume of air. OK enough semantics, sorry all.

 

[ericj]

Quote:

Originally Posted by AzN1337c0d3r /img/forum/go_quote.gif Just FYI, Printed Circuit Boards are usually composites composed of either cotton paper or glass and epoxy resin. Furthermore they are usually laminated with PTFE (aka teflon).

Where'd you get the idea that there's PTFE in circuit boards? Never heard of such a thing.

The cheap ones are basically paper bound together with phenolic resin, the good ones are fiberglass & epoxy. PTFE may enter into it in some specialty applications but would be extremely rare.

 

[spritzer]

You can special order PTFE and even silver for circuit boards from some board houses but it is horrendously expensive.

 

[Shoewreck]

The diaphragms may be lighter than air they pressurize or move, not air they displace. Dynamic diaphragms are much heavier.

 

[John Buchanan]

Quote:

Originally Posted by phkd /img/forum/go_quote.gif they technically can be lighter than air... if you define the amount of air properly. But as the poster above me said it, they certainly are less dense than air, making them heavier than an equal volume of air. OK enough semantics, sorry all.

Shouldn't that be ".....they certainly are more dense than air, making them heavier than an equal volume of air" otherwise they would be floating away like a helium filled balloon, which, on average, is less dense than the air it displaces.