[dinosauract]

Found the following in a link provided in another thread.

"The AHD-950 is an around-the-ear closed-back stereo headphone designed for both high-end hi-fi audio and for professional monitoring. Large 50mm driver units deliver deep bass, low distortion, wide dynamic range and a frequency response of 2Hz to 31kHz. Low resonance driver housing enclosures guarantee faithful reproduction of the source material, and vaporized diamond diaphragms provide outstanding high frequency resolution. "

How do you vaporize diamond? And the technology and materials involved don't seem like something you'd find in any product which costs one or two hundred dollars. I've seen this "vaporized diamond" thing before, is it just marketing mumbo-jumbo? That frequency response is pretty wild, too.

 

[pedxing]

Sounds like the typical marketing blurb found on the back of most mass consumer-end headphone products. If you like pick up and read the blurbs to Sony ear buds, you might encounter the same type of blurb. For example, a small pair of $20.00 sony ear bud that I bought like three years ago had a blurb that closely resembled the one you have just encountered. It said that the response frequency of +/- 3db is between 10Hz to 27KHz. They sound boomy with tinny highs and they were not very neutral. In otherwords, the specs on the box is mostly meaningless and won't tell you how the product performs.

 

[GanChan]

Doesn't something disappear when you vaporize it? It's the new patented, invisible nonexistent diamond! "There MAY have been diamond here, but we vaporized it to ensure maximum sound quality."

 

[Number9]

Check out Avalon Acoustics

They supposedly use tweeters with varporized diamond dust, and this technology has been trumpeted in some of their press releases for their top-of-the line Eidolon - which can go to 100khz.

 

[chillysalsa]

Not knowing anything about this product, I guess they mean it uses diaphrams with a fine diamond coating. Diamond is composed of carbon in a tetragonal lattice structure, it's like any crystal, but made of carbon atoms. If you heat up a carbon rod (basically a piece of charcoal) to a high enough temperature, you can evaporate the carbon. If you do this in a vacuum chamber, and cool down the object you want to coat (the headphone diaphrams), you will deposit the carbon onto the object. If you do it under the right conditions, the carbon will arrange itself in a tetragonal structure, giving you a diamond coating.

That's my shot at an explanation.

It's a process that's used more for putting diamond coatings on expensive camera lenses, but I know of some ultra-high frequency tweeters that are made of vapour deposited diamond on piezo-electric transducers.

Cheers

 

[dinosauract]

Thanks for the information. I knew that diamonds were composed of carbon, but I didn't realize that they could be "synthesized" from other forms of carbon in a controlled fashion like that.

It still seems surprising that an inexpensive consumer product would use that tehcnology. I suspect the "diamond" term is used pretty loosely here.

 

[Number9]

Inexpensive is relative.

The Eidelon's are not cheap. Suppsodely, the vaporization process is very expensive.

 

[GanChan]

If diamond is such a hard substance, wouldn't its rigidity prevent it from resonating or vibrating within desirable performance levels? Or have I got my brain stuck up my nose again? Someone give me a lesson in geo-acoustics.

 

[wallijonn]

instead of sand balsting, or sand-paper-ing down a diaphram to the correct thickness (polishing), you'd use diamond dust because a laser would defract in the cutting process, possibly creating heat and cold spots. of course i'd be more interested if they used a copper core with oxygen free copper wiring, instead

 

[Budgie]

Hell of a guess, Chillysalsa!

http://www.zyvex.com/nanotech/diamondCVD.html

 

[chillysalsa]

Not really a guess, I'm a materials engineering student.

I've recalled who makes those diamond tweeters: Accuton!

Here's more about them from their site:

http://www.accuton.com/

Diamond membranes – in theory – have always been the dream of louspeaker engineers because the physical properties of cristalline diamond represent the ideal of an acoustic transducer:

diamond is the hardest natural substance on this planet. It defines the top (=10) of Moh’s scale of hardness. It is still about 5 times harder than our extremely hard ceramic membrane, which in fact consists of corundum, i.e.opalescent sapphire, which defines the (=9) on Moh’s scale.


the internal sound velocity of diamond is faster than in any other natural substance. This is one of the main features that makes a diamond membrane so desirable for audio transducers. This extends the linar range of transducer a lot, in this case (D²20-6) up to 100 kHz.


diamond conducts heat better than any other material in this world, still 5 times better than silver, the second best . It represents the best conceivable heat sink for the excessive heat of a moving voice coil. This means that the voice coil will operate always under the same stable conditions without variations in impedance or Rdc.


the carbon atoms in a diamond lattice are packed closer together than any other atoms or molecules in any other material. This makes material bonding stronger than anything else and yields unsurpassed transient response.


diamond is resistive against all kinds of aggressive materials and wear. It also has the highest melting point of all natural substances. A diamond membrane - treated properly - will potentially last for a couple of million years.

 

[Duncan]

This has been a genuinly interesting read so far, thanks guys...

One thing that did make me laugh though was this...

Quote:

A diamond membrane - treated properly - will potentially last for a couple of million years.

I'll have to remember that for Christmas