JVC's Micro HD Line: HA-FXD80/70/60 - Page 8

Finally got a chance to scan / upload that page about driver materials. I suppose you want to click on it to actually be able to, you know, read it:

Diamond is off the charts there.  It's a shame Sony stopped using it, and Yamaha stopped using Beryllium.

Originally Posted by tomscy2000 

 

No, it is 'real'... it's just not what people might think... think of a lot of very, very tiny little carbon fruit loops glued onto the surface of a diaphragm...

I don't think that would retain the stiffness to weight ratio and consequential detail / resolution etc.

It doesn't say carbon nanotube coated it says carbon nanotube lol.

 <-- pure wood center in the FX500 (not coated)

This quote(taken from the JVC America press release)...

"Carbon nanotubes diaphragms represent a breakthrough in headphone technology as the material provides a balance of strength and flexibility that cannot be matched by diaphragms made from metals or plastics.  When paired the large 8.5mm driver units in the HA-FX40, the result is exceptionally crisp, detailed full-range sound, particularly in the mid-high frequency range."

...pretty much says it is the driver material and not any type of coating.

Quote:

Originally Posted by jant71 

This quote(taken from the JVC America press release)...

 

"Carbon nanotubes diaphragms represent a breakthrough in headphone technology as the material provides a balance of strength and flexibility that cannot be matched by diaphragms made from metals or plastics.  When paired the large 8.5mm driver units in the HA-FX40, the result is exceptionally crisp, detailed full-range sound, particularly in the mid-high frequency range."

 

...pretty much says it is the driver material and not any type of coating.

Not really. The entire press release never states: "We only use carbon nanotubes to make the diaphragm". The release states 

a) Carbon nanotubes are great material

b) We are using carbon nanotubes in our driver diaphragms

If Sony or Samsung says "we make our screens out of Corning Gorilla Glass", it can be assumed that they are referring to one material out of many that comprise the LCD assembly.

If you google the phrase "jvc carbon nanotube coated" you will actually see that many of the listings of the HA-FX40 contain this line of marketing copy:

While this marketing copy appears to have been changed (not least because it doesn't really make grammatical sense) it does suggest that the original marketing copy sent out to retailers reflected that the diaphragm is coated, not composed entirely of carbon nanotubes.

This is not to say that carbon nanotubes diffused over some other diaphragm substrate is 'inferior' to making the entire thing out of nanotubes. Again, I doubt many of us have the engineering experience and expertise to know if it would even be possible or beneficial to do such a thing. While it might appeal to our idea of 'design purity' that the entire driver be made out of some specific material, that's really wishful thinking and armchair engineering.

Here's an example: this interesting B&W video explains why they chose diamond as their material to make tweeters, and specifically refers to what effect driver stiffness has on tweeter design.

You would be forgiven for thinking, both from this video and B&W's description of the technology here,

http://www.bowers-wilkins.com/Discover/Discover/Technologies/Diamond_Tweeters.html

That B&W literally makes tweeters out of pure diamonds. 

And yet notice this passage in the marketing copy:

Notice the analogy - ice-crystals forming on a window. So what's CVD? From the wikipedia article about synthetic diamonds,

So. The B&W 'Diamond tweeters' are formed by diffusing carbon onto some other substrate. I don't think anyone is going to tell B&W that their tweeters suck because they aren't pure diamond, but their marketing copy simplifies the process because the idea that the entire diaphragm is made purely of diamond is innately appealing to their target consumers.

Similarly, I don't think JVC is going to dilute their message by suggesting their drivers are made out of carbon nanotubes diffused onto a polymer substrate, instead of going with "CARBON NANOTUBE DIAPHRAGMS DELIVER CRYSTAL CLEAR SOUND!". Sony isn't going to tell anyone exactly how liquid crystal polymer is used as a substrate compared with bio cellulose grown on Vectran, etc.

Even the wood driver in this diagram appears to be a thin membrane of wood over that plastic substrate. Why do I say that? Because the wood is so visibly thin in parts that if there was no substrate, the diaphragm would essentially be porous and in a non-uniform way across the driver surface. I'm sure that would create all sorts of distortion and directivity issues if a diaphragm could not be made in a consistent repeatable manner. (Honestly synthetic and uniformly grown bio-cellulose membranes sound like a better idea than making drivers out of organic and irregular wood membranes anyway).

Now, I have no idea how bonding one material to the other means that the polymer substrate doesn't just become 'the weakest link in the chain' by resonating before the superior wood / diamond / carbon nanotube does, but this is something I would suggest the engineers have a better idea of. 

Yeah, JVC invented the grammophone (so basically, audio) and the first TV in Japan (so... basically, visusal) and have you seen their latest 3D cameras?

They don't need to hype some little IEM, this is real space elevator sound, get your angel trumpets ready.

Originally Posted by a_recording 

 

［／］

 

 

Even the wood driver in this diagram appears to be a thin membrane of wood over that plastic substrate. Why do I say that? Because the wood is so visibly thin in parts that if there was no substrate, the diaphragm would essentially be porous and in a non-uniform way across the driver surface. I'm sure that would create all sorts of distortion and directivity issues if a diaphragm could not be made in a consistent repeatable manner. (Honestly synthetic and uniformly grown bio-cellulose membranes sound like a better idea than making drivers out of organic and irregular wood membranes anyway).

 

Now, I have no idea how bonding one material to the other means that the polymer substrate doesn't just become 'the weakest link in the chain' by resonating before the superior wood / diamond / carbon nanotube does, but this is something I would suggest the engineers have a better idea of. 

Why are you guys being so cynical to marketing and price?

I don't know why bio-cel is a better idea than wood all of a sudden due to uniformity issues.  If you want uniformity and low costs you make everything out of plastic.  None of the JVC wooden series are truly uniform since they're made out of trees, however uniformity and the manufacturing process aren't relevant to the design in these products.

Even in plastic, it's not like Sony layered polyethelene and polyimide several hundreds of times since they thought it was fun and they'd make more money like that.

Quote:

Originally Posted by kiteki 

Yeah, JVC invented the grammophone (so basically, audio) and the first TV in Japan (so... basically, visusal) and have you seen their latest 3D cameras?

 

They don't need to hype some little IEM, this is real space elevator sound, get your angel trumpets ready.

Here's hoping it will be real Charlie and the Glass Elevator stuff! :3

I'm looking forward to tomorrow.

1) WWDC (Means I'll be buying a new computer)

2) JVC Pre-order should ship out from Amazon JP

3) MA900's should arrive

Yay!

By the way the E888 is pure bio-cellulose, you can see it.  So is the Vsonic GR07 according to the explosion picture.

I think the EX600 / 800ST / 1000 are mostly successful due to their architecture, which is another factor intertwined with driver material, anti-/resonance.

Of course you need thick cables, high current, high voltage, and some vitamins to hear any of this at all, lol.  =)

Oh well, leftover angel salt or real space elevators, the primary reason I'm interested is the driver distance - http://www3.jvckenwood.com/accessory/inner_sp/fxc71_51/sound2.html?p=1

The human ear isn't an anechoic chamber, so you either need an IEM / custom IEM with anechoic interior design (Sony = magnesium / Starkey = patented tubes) or deep diver insertion.  IMLE.

Quote:

Originally Posted by kiteki 

Oh well, leftover angel salt or real space elevators, the primary reason I'm interested is the driver distance - http://www3.jvckenwood.com/accessory/inner_sp/fxc71_51/sound2.html?p=1

 

The human ear isn't an anechoic chamber, so you either need an IEM / custom IEM with anechoic interior design (Sony = magnesium / Starkey = patented tubes) or deep diver insertion.  IMLE.

While this seems like a good idea in theory, I wonder how it jives with the observation in full size headphones that increased driver distance - especially at an angle to the ear - improves soundstage because it allows low frequency waves to fully propagate and interact with the shape of the outer ear, resulting in all kinds of psychoacoustic fun.

Quote:

Originally Posted by tomscy2000 

Well, I guess it can be carbon nanotube sheeting, which is small threads of the tubing woven together... I'm not denying it's cool stuff, but JVC's not the one producing it. For them to be used in such small diaphragms, I'm very willing to bet that JVC is buying up the scraps otherwise used in aerospace, research, etc. all the sheeting that has been deemed not big enough or not up to standards for high-tech use.

IEMs made of SPACESHIPS (rejects)? awww yeaaa~

Originally Posted by a_recording 

 

While this seems like a good idea in theory, I wonder how it jives with the observation in full size headphones that increased driver distance - especially at an angle to the ear - improves soundstage because it allows low frequency waves to fully propagate and interact with the shape of the outer ear, resulting in all kinds of psychoacoustic fun.

The SA-5000, T5p and Ultrasone S-Logics just sound pretty much like any other headphone, to me.  Edit:  Unless you mean the K1000.

The difference in presentation between full-size speakers, headphones (of any kind), IEM's and then custom IEM's is pretty vast.

I'd say the K1000 is between headphone and speaker, and the MicroHD is between IEM and CIEM.  That's my experience at least, not theories.