Yes/No visualizes sound waves traveling through air, in a very detailed sculpture made of steel. CarstenNicolai used recordings of Laurie Anderson saying "yes" and "no" as input while creating this sculpture. You can clearly see the difference between vowels and consonants.
I've known Carsten Nicolai quite well for his work as Alva Noto, and his collaboration with Ryuichi Sakamoto, among others. He often explores the relationships between the visual and the audible in his projects. He also published a book, Grid Index, earlier this year.