Signal2Noise
Headphoneus Supremus
Apologies if this has been posted already but I did a search. Honestly!
How £1,000 headphones are made: A Sennheiser factory tour - Page 2 - Crave at CNET UK
How £1,000 headphones are made: A Sennheiser factory tour - Page 2 - Crave at CNET UK