MIXTUR (1964; the CD contains the usually performed version for small ensemble 1967) 

for orchestra, 4 sine-wave generators and 4 ring modulators

MIXTUR is a work where the sound of an orchestra playing live is mixed with electronics and the resulting sound mixture is reproduced by a group of loudspeakers in the concert hall. The audience sees the musicians playing, but the sounds heard are entirely different from what you normally would expect from an orchestra.

The composer wrote in 1965:

"In MIXTUR [...] the pitches of a wood-wind group, a brass group and of two string groups (one plays predominantly arco, the second pizzicato) are picked up by 4 groups of microphones and circuited to 4 mixing consoles, where sound engineers control the balance of the individual microphones and the sum of each group.

"The outputs of the 4 mixing consoles are circuited to 4 ring modulators. Four musicians 'play' sine-wave generators (beat-frequency oscillators), whose sine-waves modulate the instrumental pitches in the ring modulators. The results of this modulation are played over a group of 4 loudspeakers and simultaneously mixed with the orchestra sound. A mixture-sound results from each instrumental sound in accordance with the score.

"What is involved, is the forming of the timbre-texture through harmonic, subharmonic or chromatic interval-parallels.

"In a fifth group, 3 percussionists each play a cymbal and a tam-tam, all instruments having contact microphone pick-ups circuited to 3 separate loudspeakers.

"Thus, refined timbre composition which until now I could only realise in the realm of electronic music is also possible when using traditional instruments.

"In addition to the transformation of timbres, any number of fine pitch differences can be composed within each half tone step of the division of an octave in use until now.

"A rhythmic transformation of the instrumental sounds results from their modulation by very low sine-wave frequencies below ca. 16 Hz.

"The further development of instrumental music seems to me now to be completely open, since the irreplaceable qualities of instrumental music especially its flexibility in the course of history, its liveliness are combined with the advances in electronic music, forming a new unity as Live Electronic Music."

The composer writes further:

"Beauty of mirrored overtone-harmonies

[] In addition the ring modulation adds to the instrumental spectra new overtone and sub-tone series which can be well heard through, especially during held sounds of MIXTUR. Such mixtures do not exist in nature and in traditional instruments. Through these mirrored overtone-harmonies one is moved to strange enchanted perceptions of beauty which are completely new in art music.

Only such renewals of musical impact give meaning to new techniques."

(The CD booklet contains a detailed explanation of how those mirrored overtone harmonies are generated.)


All kinds of musical motion are experienced through the 20 moments into which the work is divided, kinds of motion already hinted at in titles such as Blöcke/Blocks, Punkte/Points, Dialog/Dialogue, Tutti, Ruhe/Calmness. There are also moments highlighting separate instrumental groups Holz/Wood, Blech/Brass, Streicher/Strings, Pizzicato, Schlagzeug/Percussion. All moments follow each other without any break; musical gestures from previous moments are often continued through the first measures of new moments.

After having gone through the useful procedure of assimilating the characteristics of the single moments, I found out that I best enjoy the music by just concentrating on the different presentations of the flow of the music throughout the work, without constantly paying attention to where one moment ends and the next begins. And a great enjoyment it is.

The mixture of orchestral playing with live electronics creates an extraordinarily powerful sound, with a special kind of "body" which is mightily filling musical space. At times, veritable masses of sound are unleashed. Very gutsy in character, the sound not only creates special power but also a special tension. The above mentioned presentation of the sound through all kinds of different musical motions leads to an always freshly fascinating experience of all facets of the sound.

The sound itself is hard to describe. The electronic component in the sound is not at all reminiscent of the sinewave generators themselves which mix their sound into the orchestral one; the overall combination of orchestral and electronic sound also does not result in anything that you would expect from a synthesizer. Rather, the overall result is more like an enchanted version of an orchestral sound coming directly from a modern fairytale. The high registers can be of very penetrating tone, in the lower ones the sound often acquires a menacingly growling character an exciting feature. Sometimes the sound also has a metallic color, maybe most explicitly audible in the moment "Pizzicato". This metallic color is emphasized and added to by the cymbals and tam-tams, which often are not struck, but scratched (this is made audible since, as the composer points out above, their sound is picked up by contact microphones and amplified). The sound overall has a fascinatingly resonant character, resonant not in the sense of reverberant acoustics, but in the sense of vibrating body within it.

Detail is transformed in the music. While the orchestral timbre is homogenized to a certain degree by the fact that the sound of nearly all instruments (percussion excluded) undergoes the mixture with the same kind of electronic signals, the effects from ring modulation (see above), including the little electronic fluctuations in the mixed output, give a new kind of detailing which purely orchestral sound does not have. The only comparison I can come up with for this phenomenon is a visual one, involving the view through a window pane wetted by rain: while details of the objects outside may be blurred by the raindrops, the little scatterings of light through the raindrops give a new detailing to the perceived picture of objects outside.

For anyone interested in all the sound possibilities opened up and created in contemporary music (that is, probably any serious contemporary music collector), the unique sound generated by the mixture of live orchestral sound with electronics makes the acquisition of this CD a compelling must. I consider it a standard work and a milestone in the exploration of new sounds.

This work seems very close to Stockhausen's heart. He has supervised in person numerous performances of the work all over the world, and he considered it as so important that he decided to have the work represent him at the 10th anniversary concert of the Ensemble Intercontemporain in Paris 1987 (at the time that he worked on the fabulous opera MONTAG aus LICHT, see my essay), where again he supervised the performance personally.

The CD contains the retrograde-version of MIXTUR (moments reversed), followed by the forward-version; both are to be played in one concert in that order. The freshness of timbre as a result of the mixture of electronics and orchestra is beguiling. Together with the good definition of sound (with the recording transparently mixed down onto CD by Stockhausen himself) it appears to belie the 1967 recording date; only some moderate tape hiss hints at the fact that this recording is not one of the newest.

An unusual wealth of information is provided in the CD booklet. In fact, it is a real mini-book which contains more than a hundred pages including more than 30 photographs (both black/white and color) as well as many excerpts from the score. A special picture is the one which shows those three giants of contemporary music, Messiaen, Boulez and Stockhausen, together after the 10th anniversary concert of the Ensemble Intercontemporain in Paris 1987.

The CD is available at (CD 8).

© Albrecht Moritz 2000, text edited 2005