Testing the Yamamoto HS-4 Carbon Fiber headshell.

I want to make it clear, you guys are talking about different materials ... Carbon-Fiber, Pure Carbon, Carbon-Graphite, Graphite etc ...

I remember headshells from OMA (Graphite) and from Thomas Schick (also Graphite) and they are different. Not to mention Graphite plinth.

I’ve seen some new carbon-fiber mat and the structure is way different that Boston Audio Graphite mat.

The designers of Boston Audio Mat explained many things here (see below), also BA mat has been upgraded 2 times since it’s first release, the latest is The Mat.

"It’s also important to understand that true carbon-graphite is not "graphite" as in carbon fiber golf clubs, tennis rackets, etc. While such products are often mistakenly called graphite, carbon fiber is a composite material with totally different mechanical properties than pure carbon-graphite.

The Mat - the last component in the record support system and the only part of the turntable capable of dealing with stylus-induced oscillation.
The stylus oscillates while reading the millions of bumps and ridges within the groove, it consequently releases a portion of that vibration back into the vinyl itself (the opposite reaction).
These vibrations saturate the vinyl and bounce off the platter and back to the stylus.

Even in the most rigorously setup and isolated turntables, stylus oscillation is a source of distortion that is hard to avoid.

Felt mats do dampen some of the vibrations generated by the stylus and help to insulate the record from the platter because of its low mass. But precisely because of felt’s extremely low mass, its effectiveness is limited.
Our search ultimately led us to a rather exotic material for a turntable mat - pure carbon in the form of graphite.

Graphite also offers one of the lowest mechanical impedance of any material in existence. Simply put, mechanical impedance is a material’s resistance to energy. Graphite’s low mechanical impedance means that energy may freely enter the material, but its loosely bound molecular layers are very efficient in absorbing and dissipating energy - be it neutrons generated by a nuclear reaction or micro-vibrations from a stylus.

In addition to absorbing and dissipating stylus oscillation, graphite is excellent at absorbing turntable-produced contamination including bearing and pulley imperfections, motor noise, platter ring and even noise generated by the belt turning the platter."

Here is a manufacturing tour.

Now let me compare:

1)

Yamamoto Carbon-Fiber headshell 

Carbon-Fiber turntable mat 

Another Oyaide Carbon-Fiber headshell 

Looking at all those pictures do you see some similarities ? 
The structure of Carbon-Fiber is the same, just like this sheet. 



2)

Now look at the Graphite mat, here is mine, but you can also look here. 

This is OMA Graphite headshell and OMA Graphite Mat. 

Thomas Schick Graphite headshell. 

And let me remind you about rare Grace Carbon-Fiber headshell. 


And let me summarize: 

The material used for products in chapter 1 is completely different from the material used for products chapter 2. Even if the Yamamoto headshell and Grace headshell advertised as Carbon-Fiber it is obvious that they are completely different and therefore have different properties. Same about Carbon-Fiber mat from chapter 1 and Boston Audio & Sakura Systems Graphite mat from chapter 2. 

I've been told that OMA Graphite headshell is also different from the Schick Graphite headshell. 

In other words saying something about Yamamoto Carbon-Fiber headshell you can't project it to the Boston Audio Graphite mat. They are made of the different material. 

Chakster, I am not sure I get your point.  Who is it that confused the graphite Boston Audio record mat for the carbon fiber Yamamoto (or Oyaide, or etc) headshell?  In addition to my two Yamamoto CF headshells, I also own the Oyaide one, just to see for myself if there is any qualitative difference in their sound(s).  So far, no.  But Noromance does not like either the graphite mat nor the CF headshell, and he knows the difference. Bill Stevenson doesn't like the CF headshell either.  You, Halcro, and I do like the CF headshell.  Yet we all (Nandric and Bill included) own very different audio equipment. Go figure.
Nandric, Don't worry. I pay for our travel to Tokyo.  About once a year, for the past 3 years, we have been renting an apartment via Airbnb, for 2-3 weeks each time.  Before that, I used to stop in Tokyo on my way to and from scientific meetings in Thailand or Vietnam, to see our son for a day or two.

Thanks @chakster and @lewm 
Yes, I'm aware of the differences. 

Dear Lew, My worry was that 30% discount for the headshells you
bought in Japan would not cover the ''other costs'' . That is why
I assumed that either your son or Japanese government paid the
''other costs''.