This remarkable recording of Stockhausen's work for chorus, Stimmung, is one of those albums that should be heard with headphones to really appreciate the particular aural dynamics of how he composed for polyphonic singing.
As performed by Paul Hillier's amazing Theatre of Voices, Stimmung is an especially stimulating experience, one that, for some, might be worth hearing after listening to, say, Le Mystere des Voix Bulgares, a Latvian female choir album, or the male Rustavi Choir from the republic of Georgia. There are also sections of overtone singing that are somewhat reminiscent of the Tuva throat singers of Mongolia.
Stockhausen composed Stimmung, which implies tuning voices but can also refer to a calibrating of the soul in a positive way, in early 1968 as his take on madrigals, using text, vocalizations, and his own particular style of composing to create something very different and new. While there is basically a single chord utilized, the use of six pitches and overtones provides a complexity that makes the piece move beyond the idea of that one chord.
Instead of a score, there is a "form scheme" with 51 models that the singers follow with instructions as to who sings, what pitches are employed, and the textual resources (including a selection from 66 "magic names" based on mythological fitures) utilized. There is a call-and-response element to the work with variations and the use of some improvisation and a new lead singer takes over in each model, though the ensemble decided which model goes where within the general scheme.
Interestingly, Hillier stated that Stockhausen offered to assist with the recording, but schedules did not permit it, so a tape of a performance was sent and the composer returned "a detailed critique—whch we found challenging and extremely helpful." This sounds very Stockhausenian, actually, as does the closing comment that the various recordings of Stimmung sound quite different from one another, which is probably to be expected given the extraordinary way the piece was worked out and the demands it places on performers to utilize their individual and collective personalities in the performance.
Finally, Hillier offers that, of all of the experimental works of the 1960s, he feels Terry Riley's In C and Stimming are most representative and that he sees these very different works as being related to the conditions of time (the Sixties) and place (the effects of California on the two men)
Stimmung is, especially heard with headphones, a particularly stimulating and compelling work by one of the most provocative and unique composers in recent decades. The recording quality is also crystalline, which really enhances the effect.