The composition is to be understood as a late commentary
on the resonating qualities of the building materials of Alfred Grenader's U-Bahn stations:
not a "Bahn"; instead, sounds in themselves.
Out of the partly still available original (glazed) tiles, a xylophone-like
instrument is constructed that fits into my remaining percussive instrumentarium.
Furthermore, sheets of metal, ornamental elements, and supports are incorporated into the spectrum of potential sounds and noises. ----- It will be a kind of "retrieval" of the exclamations that have been absorbed by the tiles in the U-Bahn stations over decades.
---- The "grenaphone" is born.