Wikipedia
Kassetten (English: Cassettes) is the fifth release of Einstürzende Neubauten's Musterhaus project, a series of highly experimental CD releases that were only available via an annual subscription through their website or from shows during their 25th Anniversary Tour. This project was separate from their Neubauten.org Supporter Project, which it ran concurrent to.
The concept of this Musterhaus release is providing a series of samples of cassette recordings that Einstürzende Neubauten has amassed over the years. As noted on the back of the album, in their earlier years every member of the band owned a cassette recorder and found it invaluable. Recorded were various audio experiments with friends, general field recordings of found sounds (such as the dismantling of a wardrobe, people entering a shop, expeditions to certain areas, etc.), tape noise experiments, answering machine recordings and nearly every interview they conducted during that time period.