6 a capella voices

Menschen, hört is a work from a cycle of seven operas composed by Karlheinz Stockhausen, Licht, subtitled “The Seven Days of the Week”. The cycle Licht consists of 29 hours of music and is constructed modularly. Not only is each of the seven operas a self-sufficient work, but so are the individual acts, scenes, and—in some cases—portions of scenes. These modules may be segments (e.g., the eleven instrumental solo sections from Orchester-Finalisten from Mittwoch), or layers (e.g., the electronic Oktophonie layer from the second act of Dienstag or the Klavierstück XIII version of the first scene of Samstag, with the bass voice omitted), or a combination of the two (e.g., the vocal sextet Menschen, hört and the Bassetsu-Trio, which are two layers of the “Karusel” subscene from Michaelion, the fourth scene of Mittwoch).

(Source: Wikipédia)