Wood and Concrete Headphones

Just a quick project using the drivers from a broken set of Sony MDR-570LP headphones. 
I have been reading about the excellent sound quality that using wood in the construction of headphones. I have also recently read an article about people making things from concrete, like speakers. This project combines both wood and concrete to form the housing for the headphone drivers.
The sound is crisp with a good range. I noticed a difference when playing live music through these so I think the materials have made a difference to the original quality of these drivers.