[BlackbeardBen]

Quote:

Nope, I doubt that. Usually carbon fiber-reinforced plastic have a shinier surface and doesn't bend that easily. It looks like plain ABS to me. 
 

Looking again and so far not seeing any fibers at all in the broken headband or on the worn parts of my own (using a 6x loupe), I don't really think so either.
 
However, the N-Gear Jump Stop, for example, is made of Zytel with fiberglass reinforcement yet is extremely flexible - so I wouldn't really have put something like the HD 600/650 headband being made with CFRP out of the question until I saw the crossection of the broken headband.
 
To be fair, Sennheiser makes absolutely no claims themselves about the material used for the headband and frame.  They say "High-quality titanium/silver finish" for the HD 650, clearly meaning the color and not the material...
 
Actually, when I look at the drivers to my HD 600 it definitely does look like fiber-reinforced plastic there.  That may be what the confusion is about...

 

[Bartmil]

A thin coat, with 2 layers of carbon fiber sheets, are prety strong and flexible!
And 1 layer inside, and 1 outside, could be enought.
And you dont need to cover all the "Haste", just 2 thin strips, between the edges.