Synthetic diamond

Synthetic diamond is becoming cheaper and cheaper and will continue to do so, until it’s relatively affordable for any given purpose.
Comes a day when it’ll be efficient to produce, say, a 12" woofer out of diamond. Can it be bested? Will it be the end of materials science development for driver cones?

Since diamond has the highest possible Young’s modulus and isn’t inherently heavy (and can be made as thin as wanted anyway), could there possibly be a better solution for a mechanical driver? Will we be left developing the optimal surround materials after diamond becomes “cheap”? (Might we also find the best surround materials from the family of carbons…?)

The driver development industry’s money has to go somewhere even after the best materials are found, so might diamond eventually shift the development from mechanical drivers to, say, plasma technology?
I sure hope so, given the potential of plasma drivers. While they already exist, they’re inefficient in all means of efficiency. And there’s no available plasma midranges yet! Imagine having the vocal range covered by a single massless driver! While we’re at it, let’s also imagine a plasma subwoofer that takes up merely as much power as New York!

Discuss the future of audio with the idea that soon enough we’ll have “cheap” diamond as a commodity.

A friend of mine designs and develops industrial speakers, and occasionally they build some very low numbers home speakers for a significant few. They are really really good, the guys who run it went to my school and are still great friends with my best friend. I’ve been over to their factory a few times and remain completely interested in their journey, especially through the pandemic when they almost had to close shop.

The company is call EM Acoustics.

Now one of the directors who is the scientist behind the project has just sourced some diamond drivers with the aim of developing some rediculous home speaker. From what I hear he’s got the design down ready, and has just ordered a couple of drivers to do some testing.

I’m so keen to hear them! I think if they were to head into the home market, they’d be incredibly successful!

I read an interesting article recently on synthetic diamond production, just trying to find the link:

Lab-made hexagonal diamonds stiffer than natural diamonds | EurekAlert! Science News

Scientists make artificial diamonds at room temperature (

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Do you know if they’re diamond “dome” type tweeters or something else entirely?
I could imagine that we could have diamond film planar drivers already today, with an inductive circuit embedded on them during the deposition process, shouldn’t be impossible in terms of size and shape… Just guessing though.
From what I’ve understood we’re currently limited to tweeters. Then again maybe a midrange driver could be assembled from several small cells of diamond? Hmm…

Ahhh yes, good ol’ Lonsdaleite!

I believe they’re dome drivers with an embedded diamond “dust” if you like to increase rigidity, but I’m not 100%. They got them from a Danish source, and IMHO, Danes are usually pretty good with audio stuff.

We’re still in a full on lockdown over here, but when it eases, I’m going to see if I can pop up there and take a look.

The cabinet work they do is nothing short of incredible, using CNC lathes to sculpt the inner cavity, it’s incredibly precise, but man, does it achieve some results. Paired with these drivers, I’m really excited to see what they can achieve.

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THESE have been on the market for the past 5 years!

A cool $7.5K can get you a custom Sierra-2Di Monitor pair like THIS !!!


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Wow! Pure diamond - I had no idea that was a thing!

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There is certainly some confusion about today’s “diamond” tweeters as in, are they diamond or more like diamond-encrusted. It’s kind of conventional for the companies using them to have this confusion as they can nomenclaturely state they’re using diamond drivers. Well, they are, just the key word here being pure.

“For example TIDAL was the first manufacturer worldwide using a 1 carat 30mm driver, already more than 13 years ago. And since 2015 we have another milestone: the worlds only pure diamond diaphragm midrange-woofer, also to find only in a TIDAL speaker. Or to say so, the biggest diamond driver in the world. At all. A 13 carat driver, covering frequencies from the upper bass all the way up into the midrange area.”


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Please post any articles on the CVD / HPHT techniques of manufacturing pure synthetic diamond diaphragms for the audio industry.
I just read a nearly 600 page Wiley Series book on synthetic diamond films, mainly electrochemistry and related applications but now I’ve a good basis to understand micro/nanodiamond preparation and properties.

For mid ranges and woofers, I think graphene might be a better choice. But, only time will tell.

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Yes, surely good enough and mainly cheaper than diamond.

There was an ad in Stereophile about woofers with an aluminium honeycomb with graphene/carbon fiber surface treatment, I think it was Magico… They praise this innovation as pure pistonic motion.

Me thinks, a a paste made from a couple of Viagra tabs and glue, painted on the cone would have the same result! :joy: :roll_eyes: :thinking:


Diamond is a brittle material compared to any metallic membrane. Yes it’s strong under compressive force (which will be the case as long as you have perfect linear motion), but quite weak under tensile stress (which will likely be the case under most circumstances).

This is why you see diamond drivers that in essence a metallic substrate with a P-CVD (plasma assisted chemical vapor deposition) coating of diamond (or DLC, diamond like coating). The purpose is to add rigidity with minimal weight.

Graphene does in essence the same thing… Graphene is basically a single atom carbon in a lattice honeycomb structure, which adds lots of strength/rigidity and no real weight. I can’t imagine making an actual driver out of graphene (it would take MANY layers) as it would be cost prohibitive. Hence graphene drivers are a substrate (seems to be some kind of composite typically with a graphene layer or layers to add strength/rigidity. The biggest difference is that graphene is strong both under compressive and tensile stresses. Hence it’s highly suitable for drivers with greater motions, such as mid-range and bass drivers.

All this really starts with the fact that carbon is used for rigidity with minimal weight added. Diamond is a carbon atom sharing electrons with another carbon atom in a tetrahedral shape, whereas graphite is a carbon atom sharing 3 electrons, hence forming hexagonal shapes. Why bring up graphite? DLC is basically a graphite structure with elements of diamond structures randomly appearing.

Hope this sheds some light on the different materials.


Diamond films could serve better in the circuit components, let’s see when we have N&P diamond power transistors…
Or very small but high-performance and resilient diamond components, long-lasting mini vacuum tubes with surprising performance, what have you. If not diamond, it’s gonna be some form of carbon occupying many of the high performance componentry.