Diamond diaphrams - Why so expensive?

[Krillin]

Diamonds are expensive, not because they are rare but because their supply is strictly controlled. Lower quality diamonds often find themselves being used for industrial purposes like cutting tools, and we have the capability of creating synthetic diamonds since they are just carbon under intense pressure and heat. So why are diamond diaphragms so expensive to implement in a tweeter or midrange? Tooling, energy costs, patents, R&D, or is it just the allure that a diamond wedding rings should cost 2 months salary so therefore so should a diamond diaphram? When are the prices going to come down?

Also, whatever happened to Dayton Audio's relationship with Usher? One would think it was quite beneficial and they are one of two manufacturers that I'm aware of that produce diamond midranges.

[Donovad]

The Spirit Wind Monitor

This design by the late Jeff Bagby has always appealed to me, and I am at a place in my life where it feels appropriate to embark on a speaker project. I know a few of you have heard these in person before and I was hoping to get some feedback before jumping in. These seem like a well kept secret that Jeff was very fond of and use some lesser known components. I intend to do something interesting with the cabinets.

His Helios is another design that I would consider that also seems rare out in the DIY Wilds.

Feedback is appreciated.

Regards,

Daniel

[Wolf]

The real deal was the real deal. No hint of issues, and very clean. If you want it done right, get the original.

The CM on the other hand did not sound right to me. The tweeter complained a bit, and the woofer sounded mistuned by PR.
Supposedly, this circuit on the tweeter was allowing stress and/or it was playing too low. I did not like it.

Wolf

[hoxuanduc]

Great. Thanks, Wolf, for giving your impression. Duc

[bking]

I believe I have the antecedent to the Spirit Wind design. Jeff Bagby was king enough to design the crossovers for my DIY speakers. They use the same drivers as the Spirit Winds and likely a similar crossover design. I can recommend them without hesitation.

[Krillin]

Diamonds are expensive, not because they are rare but because their supply is strictly controlled. Lower quality diamonds often find themselves being used for industrial purposes like cutting tools. We have the capability of creating synthetic diamonds since they are just carbon under intense pressure and heat. So why are diamond diaphragms so expensive to implement in a tweeter or midrange? Tooling, energy costs, patents, R&D, or is it just the allure that a diamond wedding rings should cost 2 months salary so therefore so should a diamond diaphram? When are the prices going to come down?

Also, whatever happened to Dayton Audio's relationship with Usher? One would think it was quite beneficial and they are one of two manufacturers that I'm aware of that produce diamond midranges.

[DeZZar]

Well I'm just adding 2 and 2 together here....but it appears to me that the equipment, manufacturing process and associated expertise required is where the cost will be. Unlike any other dome material which can just be stamped out of a sheet of whatever substrate is being used a diamond tweeter....well....to quote:

"The diamond is grown synthetically directly from methane and hydrogen gas using a carefully-regulated process called chemical vapour deposition (CVD), which involves heating the gases to very high temperatures (2000-3000°C) in a chamber, so that their carbon–hydrogen bonds break down to produce a carbon plasma that can grow a dome-shaped substrate in the chamber"

Doesn't sound like you can just head down to your local industrial equipment supplier and buy the diamond vapour deposition machine...

The cost is unlikely to never come down. It's a highly specialised product with virtually no demand and pretty limited competition.

I could be wrong though, maybe I can grow diamond tweeters in my garage with home depot supplies??


I don't think it's the holy grail of tweeter materials though....if it was you'd expect to see more of them in the 'money is no issue' high end. I've heard the B&W's - and as expectional as the system was, it was no more or less so than its competition without diamond tweeters.

[billfitzmaurice]

So why are diamond diaphragms so expensive to implement in a tweeter or midrange? .

They're expensive because people will pay the price. I bet 90% or more of those who do pay the price are unaware that they aren't made of solid diamonds but are actually coated with diamond dust.

[Krillin]

Yes, I agree it's a highly specialized product however the material itself like Bill posted is just diamond dust. Outside of De Beers control is actually quite cheap and the lower grade diamonds which are useless for jewelry are often sold cheap for cutting tools. Also, heating in a chamber to 2000-3000°C doesn't sound too complex we do it in ceramics all the time. Pure kaolin (porcelain) can fire up to 1800℃. Beryllium has come down in price so diamond can too.

Moderators, please merge my two nearly identical threads on this topic. Creation of two was due to a website error. Also, please delete my post #2 on each.

[johnnyrichards]

Yeah, vapor deposition is expensive. It won't be cheap, ever.

Every manufacturer needs their hard to duplicate cone/dome material process on their high end stuff I guess.

[Krillin]

So it's simply the tooling required for vapor deposition that is expensive. So if the one or two suppliers with these vapor deposition machines determined they could make more money by supplying the whole market prices would go down. I think this happened with beryllium too right? Isn't there only one or two suppliers of beryllium?

Yamaha made their Beryllium domes with vapor deposition in the 1970-90's. Has the industry moved onto rolled foil diaphragms for beryllium?

Finally what about DMD diamond? Really wish that Dayton had kept that Usher relationship for their own products.
https://pearl-hifi.com/06_Lit_Archiv...io_Diamond.pdf