The work is for electronic music and trumpet, soprano, bass clarinet and bass, with a duration of about 96 min.
"SIRIUS, the alpha star of Canis Major – 8.7 light years away – is the central sun of our local universe. 200 million suns with their planets and moons circle around it and live from its light.
"For the inhabitants of SIRIUS, music is the highest form of all vibrations. For this reason, music is there the most highly developed. Every musical composition on SIRIUS is linked to the rhythms of the star constellations, seasons of the year and times of the day, the elements, and the existential differences of the living beings.
"The music which I have composed and named SIRIUS transfers some of these principles of musical form and structure to our planet. There are 3 stages in this work:
The composer comments further:
"The WHEEL of the constellations and seasons is the clock of SIRIUS. 12 melodies of the zodiac are the signs of the months. According to the season of the performance, the WHEEL begins with one of the four main melodies: ARIES or CANCER or LIBRA or CAPRICORN."
Remarks by the writer of this essay: the work is based on the twelve melodies of the composition TIERKREIS (Zodiac). In the Summer Version heard on the CD the Wheel begins with CANCER.
"The WHEEL lasts over an hour. Each of the four main melodies reigns for approximately 1/4 hour, and the 12 melodies divide the hour like the 12 numbers of a clock. The WHEEL turns clockwise.
"Everything in the WHEEL is continuous change and transformation. The rhythm, melody and timbre of ARIES, CANCER, LIBRA, and CAPRICORN transform into one another independently and sometimes together. Also, one melody is always approaching as another is departing, while the third and fourth melodies rise to the surface softly or only briefly. Everything is formed from these 4 melodies. The other 8 melodies of the ZODIAC appear only by themselves – 2 in each season – and are not utilized for metamorphosis."
The melodies for the four seasons are:
1. Cancer (main melody) – Leo – Virgo
2. Libra (main melody) – Scorpio – Sagittarius
3. Capricorn (main melody) – Aquarius – Pisces
4. Aries (main melody) – Taurus – Gemini
Melodies from other seasons may also play a role in a given season.
"I made the musical realization of the electronic music for SIRIUS in the studio of the West German Radio station (WDR) in Cologne from July 1975 until March 1977. By listening to this music, in particular to the WHEEL, one perceives how the newly discovered means and structural possibilities of electronic music can awaken in us a completely new consciousness for revelations, transformations, and fusions of forms, which would never have been possible with the old musical means, and become increasingly similar to the art of metamorphosis in nature."
The electronic music was composed and realized as an 8-channel tape. In a live performance, the electronic tape is reproduced over loudspeakers mounted on towers surrounding the audience. Also surrounding the audience are the four soloists, each one located on a different side of the hall, at the 4 points of the compass. The soloists stand on podia. A firmament is projected against the ceiling of the hall. Alternatively, under favorable circumstances the performance can take place out of doors under a nocturnal sky, for example in the inner courtyard of a building (as happened at the first performance of the complete work in a cloister in France, see CD booklet).
SIRIUS is a kind of science-fiction story in which four messengers from Sirius land on Earth, teach the humans about the music on that star and after that take off again into space.
A huge subterranean bass sound, flickering like the air above a hot surface in sunlight, opens the work. It seems to be the engine of a big mothership coming from outer space. Four consecutive swirling sounds of higher frequency, sounding like a mix of helicopter engines and turbine sound, each slow down, lowering the frequency until they stop. These apparently represent the smaller ships that transport from the mothership the four messengers from Sirius descending to Earth. Finally all engine sound stops, silence ensues.
At once, a resonant, brightly shimmering percussive sound is unleashed, an electronic sound evoking impressions of a giant triangle being struck. In a grand manner, the bass introduces himself as being North, the earth, winter. Subsequent appearances of the big percussive sound mark the entrances of the trumpet – East, fire, spring –, the soprano – South, water, summer –, and the bass clarinet – West, air, autumn. Especially impressive is the blending of the trumpet timbre with the introducing percussive sound, causing an illusion of the trumpet sound to directly emerge from the percussive strike. The trumpet and the bass clarinet, not being able to express themselves in words, are introduced as characters by the bass and the soprano, respectively. The bass finally announces: "We are messengers from Sirius, our mother sun. Perceive in our music the sound of the directions of space, the sexes, seasons, phases, suns." The soprano continues: "May the music of Sirius be the felicitation to the pioneers on Earth and in space – may a more divine mankind come out of your works."
The PRESENTATION, as this first section of SIRIUS is called, must be one of the grandest openings in all music, imposing in stature. The entrances of the four characters are striking, and the evocation and breath of drama in their individual presentations is phenomenal. The drama is aided considerably by the addition of real-life sound scenes for each season, each represented by one of the four characters – footsteps in the snow, breaking of ice for the winter; incension of fire and the crackling of burning wood for the spring; falling water and a lively brook for the summer; the rushing of wind for the autumn. All these are impressively recorded and reproduced.
After the evocation of the sound of space-ship engines at the very beginning, the electronic music, apart from the percussive strikes at the four character entrances, confines itself to installing the presence of an unobtrusive dark drone that persists through the entire duration of the character presentations. Only towards the end swelling sounds are heard, further enhancing the dramatic tension that penetrates the music.
The presentation ends with the introduction of the melodies for each season, the four main melodies of the work, "Aries" for spring, "Capricorn" for the winter, "Libra" for autumn, "Cancer" for summer (see above).
Subsequently the Wheel of the constellations and seasons begins (see the composer above), which constitutes the largest part of SIRIUS. With the words of the bass "...and as summer comes out of spring" its first section CANCER enters – very dramatically. It seems as if we are suddenly swept along with a raging torrent of music.
The electronic music kicks into high gear, particularly in the now introduced strand of sped-up melody in the very high register, and all the four soloists sing/play in overwhelmingly dense counterpoint against each other, with the musical energy lead by the soprano voice. The overall pace of the music becomes very tense and agitated. This new scenario pushes the listener into total submission to the developing proceedings: keeping intensely concentrated on following the stream of the music, or drowning in the swallowing mass of sounds colliding. The music is in a state of no-holds-barred, relentless, clashing polyphony with counterpoint in the most emphatical sense of the word. The major presence of the pugnacious ARIES (ram) melody especially in the beginning of this passage seems no coincidence (during the passage, the emphasis in the polyphony gradually will shift to CANCER as being the main melody).
This dense and agitated scenario most strongly reminds me of the similarly no-holds-barred, relentless polyphony of Beethoven's Grosse Fuge (Great Fugue) op. 133 for string quartet, even though the details of the polyphonic structure are quite different. There is an equally impressive clashing of voices against each other, an equally impressive sweeping stream of music, and an equally impressive inward concentration of the music to produce an exciting, synergistic end result; there is an equally unanimous building of architecture by all voices notwithstanding the force of the music, instead of a falling apart of the fabric into uncontrolled cacophony. It is quite unbelievable with which organic ease and seamlessness as well as overall fluidity, despite all the clashing of voices, the music pushes forward throughout this entire initial passage of the Wheel, which will last eight minutes. If this is not consummate compositional mastery, then what is?
The number of voices in the polyphony is staggering. Not only do we have virtually constant playing and singing of the four soloists, the electronic music always moves in at least two voices, one in high register and one in lower middle register, and often three voices are present.
As in this initial phase, the electronic music throughout the entire Wheel is engaged in intense transformations of the melodic material – see also the comments by the composer above. The melodic contours are sometimes clustered into swarms of notes flying by with extraordinary speed (such as in high registers in the above described first passage of the Wheel), and they are compressed and expanded on continually shifting pitch scales without discrete steps – all metamorphoses that are impossible to achieve with traditional instruments. Expression of melodic lines on rhythms of other melodies, featuring continuous transformations within such processes, also is employed. Virtually all the time throughout the Wheel, with a few exceptions, the electronic music will form a continuous stream of sounds, glueing the entire music of SIRIUS together on a magic string.
Certainly, the electronic sounds do not quite spread the revolutionary aura of those in KONTAKTE, where completely unique means of sound generation were used – here they are recognizable as coming from a quite common electronic instrument, the synthesizer. Revolutionary, however, are the transformation processes in the electronic music as they are described above.
The tones sounding from the electronic music mostly show clear attack, as one would expect from keyboard instruments such as piano and clavichord (a sound character that lies within the possibilities of a synthesizer but which is not a necessary sonic result from such an instrument). This is certainly fitting in providing the necessary clarity for the continuous expression of quickly evolving melodic lines as carried by this music.
Even though they are recognizable as coming from a synthesizer, the timbres of the electronic music are unusual, I have not heard similar ones elsewhere. The more one gets acquainted with the electronic timbres the more fascinating they become. The music often sounds to me like Morse codes coming from outer space, a sound character that seems in great accord with the visit of the messengers from Sirius to Earth, the story told by SIRIUS.
The melodies of TIERKREIS, on which SIRIUS is based, originally were written for music boxes. I cannot escape the impression that the sound world of music boxes also somehow resounds in the electronic timbres – yet to remarkable effect transformed into something entirely different and new. At least I hear such character in the music of the middle to high registers (later in the Wheel, electronic music will also acquire prominence in low registers).
The synthesizer used to create the electronic music on SIRIUS was the big EMS Synthi 100, the first instrument at that time with expansive sequencer capabilities. These capabilities were crucial in the realization of all the transformations of melody, rhythm and timbre as composed in the work.
The EMS Synthi 100 can be seen in the synthesizer museum on the web.
For more discussion of the electronic music of SIRIUS, including further comments by the composer, I recommend the article "From Tape Loops To MIDI – Stockhausen's 40 Years of Electronic Music" by Michael Manion.
After the intensely dense eight minutes of clashing contrapuntal flow at the beginning of the section CANCER the music finally relaxes and, in order to make an incisive cut supporting the change of musical character, the electronic sounds slowly fade out in volume to a very low level and then start to swell into the music again. The electronic music is engaged in representing a continuous stream of rapidly evolving melodic contours, and the fading out and in of such an agitated musical line creates a remarkable sonic effect. It is aided by the emergence of more sustained tones in the electronic music during that process.
The soloists start to resume activity with the presentation of the LEO melody, and with this the music acquires some polyphonic density again. Yet immediately afterwards the texture scatters into more individual phrases by the soloists, expressed in leisurely pace above the quite rapidly moving electronic music. The appearance of the LIBRA melody introduces a more stable momentum; however, as soon as this happens, the momentum changes completely. Frequent stops are introduced in the music, at times dramatized by a kind of "jumping" switch-clicks in the electronic part. What makes this situation so special and powerful in effect is that there is still dense polyphony between electronic music and the four soloists who all sing/play different melodic lines simultaneously. Thus, whenever the music restarts, all the voices immediately resume their clashing against each other as if nothing had happened, and upon stopping all the activity is silenced at once. Since at some points the music only restarts for a few seconds before it stops again, truly striking textures are created in this manner. The music develops in this way for a few minutes.
A similar device, constant stopping and restarting of dense polyphony with complete pauses in between, has been employed by Stockhausen before in the Clapping-moment of MOMENTE. In SIRIUS, however, the sonic effect is an entirely distinct and novel one, since the context is so different. Whereas in the mentioned section of MOMENTE the polyphony creates a more textural impression, in this passage of SIRIUS we deal with multiple distinct melodic lines that are fully restarted simultaneously every time after a complete halt.
Eventually, the appearance of the graceful VIRGO melody reintroduces fluidity into the music. Following this presentation, the main thread of the music resumes and gradually also picks up fluidity again. Finally the music streams into a long cadenza that features electronic music with at first prominently, then solely, bass clarinet, in preparation of the next section LIBRA, autumn, the season that is represented by this instrument. The electronic music moves in a "Morse code" rhythm and speeds up tremendously in this mode; during this process, its sound becomes more distant and it shifts to high-pitched timbres. The bass clarinet plays variations on the LIBRA melody that show frequent brief leaps towards high pitches, thus making a gesture of approach to the electronic music. However, a strong overall impression is created of great contrast between the warm and up-close melodious playing of the bass clarinet, and the machine-like and distant sounding electronic music, and in addition to this, of a great contrast in time layers (apparent speed of musical motion), with the electronic music moving so fast. Among passages where two completely opposed strata of music simultaneously run in parallel for an extended time, this may be one of the most impressive in Stockhausen's oeuvre – and in all music, for that matter.
The cadenza leads to the section LIBRA, which reintroduces polyphony of all musical forces involved in the work; different zodiac melodies are expressed simultaneously. Now, however, the tone of the music is far more relaxed than during the frenetic activity at the beginning of the section CANCER, not the least also since the high registers in the electronic voice here do not run on a separate fast-paced course, and gradually it becomes clear that there is a tendency of the music to pull towards homophony. According to the main melody of this section, this implies a tendency towards the presentation of the LIBRA melody alone. The tendency toward homophony is in agreement with what the melody LIBRA seems to stand for; its beautiful representation of musical balance appears to call for overall harmony.
After the total polyphonic friction at the beginning of the section, gradually two or more voices at a given time – not always the same ones – start to lean towards a similar simultaneous presentation of the same melodic line. This approach to homophony is of an extraordinarily seamless quality; unless painstakingly paid attention to, it goes unnoticed in its intial stages, and the tension between polyphony and approach to homophony remains vidid for a considerable amount of time. The process is masterfully composed.
Eventually, quasi homophony is accomplished when the LIBRA melody is presented by the two pairs bass/bass clarinet and soprano/trumpet alternating with each other from phrase to phrase, with one layer of the electronic music playing the same melody. As a final achievement of the entire process unfolding since the beginning of the section, quasi homophony of all the voices at once is realized a little later, when a variation of the LIBRA melody is presented in solemn augmentation, approximately one fourth into the section, just before the SCORPIO melody appears. The harmony between the voices in the music is shortlived, however, and is violently disrupted at the end of the presentation of the SCORPIO melody. Following a trumpet signal, the electronic music, after having leisurely moved in lower middle registers for a while, suddenly breaks out into high registers accompanied by precipitated, frenetic motion. The pace of the soloists runs parallel to this change of motion, and this brief episode comes to a halt when the soprano ends up being out of breath and the bass asks her: "Cancer, are you hurt?" This is followed by the presentation of the SAGITTARIUS melody; the ensuing long build-up of again more polyphonic agitation in the music – diverting from harmony between the voices once more – leads to another abruptly disrupting passage when bass clarinet, electronic music and bass suddenly burst out into frenetic activity.
After this outburst, the music immediately seeks calm in another augmented presentation of the LIBRA melody in quasi homophony. The calming reaches a further stage when in turn this presentation is gradually and in an artful manner smoothed out, as in all voices the music flows into more sustained notes. Finally, the section LIBRA ends with sounds of wind (according to the element air represented by LIBRA), above which at last the soprano solemnly whispers "Capricorn", announcing the next section of SIRIUS.
The more the section LIBRA had progressed, the more there was a tendency of the electronic music to drift into lower registers. Along the way, the correspondence of the timbre of the electronic music to that of the bass clarinet, while maintaining its own strong identity, was breathtaking at times. Continuing the trend, the use of low registers in the electronic music will find its most powerful and expansive expression in the following section.
This section, CAPRICORN, begins with rhythmically vivid playing of the electronic music in low registers, yet with a clear and resonant contribution of middle frequencies to its spectrum as well, resulting in a remarkable sound. The electronic music presents the CAPRICORN melody while the bass (Capricorn) announces that he is coming. Then, with a very low voice, singing first in English and then in German, the bass repeats this melody twice in homophony with the electronic music, which had added considerable weight in the low register upon entry of the bass voice, resulting in thundering timbre. Such a synchronization of low bass voice with low-registered, mighty instrumental music in lively rhythm must be unique, and it certainly is an extraordinary, powerful sonic experience.
The soprano supports the music with more sustained tones, and trumpet and bass clarinet play accompanying figures. After the introduction of the CAPRICORN melody as described above, the music of the soloists moves to more broadened melodic lines for some time. During this, the electronic music – sometimes rather receding into the background – holds on to a quite lively rhythm most of the time. However, gradually its melodic line becomes pitch-compressed (as this happens without discrete steps, it is a transformation unique to the possibilities of electronic music). Finally, soprano and bass talk with each other, a conversation resulting in the decision to "come to the middle and sing the melody of AQUARIUS together". This is another musical moment of great power, since during the conversation the now again quite thundering, low-registered electronic music in lively rhythm is sustained as melodic voice, playing loudly – a remarkable invention.
After a while, the AQUARIUS melody proper enters, a melody with a beautiful swaying motion. This motion is supported in a colorful manner by the accompanying bass clarinet and trumpet. After that, the soprano tells the bass to "please be quiet for a moment" and sings the PISCES melody, in beguiling polyphony with the acoustic instruments which subsequently take over the melody in duet.
Following this, all musical forces become active again, but quite tentatively, mainly in long held notes (with exception of the electronic music). A clear heightening of tension is noticeable, slowly but steadily adding intensification to the music in anticipation of something big and substantially different to happen – possibly a climax, even though at this stage not for certain yet.
Very uncommon and highly original, however, is how this develops in its intial stages. Practically entirely without the usual increase in dynamics or brightness of color in middle or high registers (only scattered bright percussive sounds, in intriguiging timbre, are added by the electronic music), the music intensifies mainly just by deep sustained notes in the bass voice and the addition of weighty long-stretched bass tones in the electronic music.
Eventually, after the tension has reached a high level already, a straightforward and clearly directional, yet long drawn-out pushing towards a climax ensues in phrases of the soprano voice and in the development of the electronic music in low to middle registers. All that is supported by sustained tones in the bass voice and the bass clarinet as well as by cutting interjections of the trumpet. With this, we have reached the section ARIES. The phrases of the soprano voice gradually grow in excitement and dynamics while rising in pitch, and the electronic music intensifies in an overwhelming manner. The melodic lines hugely accelerate to multiple speed of the original. The resulting sound band glides to higher registers in such a way that the final result is a towering wall of sound, almost like a giant standing wave with an incredibly rapid inner fluctuation. The sonic effect created here is overpowering. Together with the soprano voice, mightily rising above this already very loud fluctuating wall of sound, and the grand sounding and commanding trumpet, the texture culminates into what must be one of the mightiest climaxes in all music. Once you have heard this, you will likely agree.
The music very slowly recedes from its utmost climactic point ("Komm Aries" – "come Aries") as Aries (the trumpet) enters and plays a variation of the ARIES melody. While subsequently the soprano intonates the same melody, the fluctuations in the electronic music slow down and in the process become more and more compressed in pitch; at the same time the music progressively softens in dynamics. The slow, continuous flattening towards one pitch in the music eventually is allowed to achieve a kind of finalization when the trumpet commences to rest on a single tone (during the last phrases of the soprano) that gradually becomes sustained, uncannily blending with the electronic music in timbre. Yet even as this trumpet tone enters, a pitch fluctuation in the electronic music keeps continuing on a subtle level, so that the now achieved, prolonged resting moment of the music still vibrates with inner life. One of the most impressive climaxes in all music has been followed by one of the most impressive calming periods in all music.
The inner life of the resting moment is additionally accentuated by continued playing, softly in the background, of the orginal ARIES melody in the electronic music. At a certain point, this melody recedes in favor of the LIBRA melody that very quietly sneaks into the music as it is intonated by electronic sounds. The electronic timbre here is fantastic – the melody seems sounding like the blowing of wind, and the air (wind) of course is the element represented by LIBRA, as heard in the PRESENTATION and at the end of the LIBRA section.
Now the music very slowly begins to regain more life as the trumpet commences very subdued playing of melody, and then changes to a more open timbre. Upon this, the vocal soloists chime in, at first with a very tentative expression and then becoming more and more firm in their melodic lines (the TAURUS and later the GEMINI melodies are sung). The electronic music also gradually re-expands its pitch range and its melodic expression. The awakening of the music as unfolding here is highly remarkable, occurring step by step and yet in such an uncannily organic way. Finally the music reaches, after this period of re-awakening, an affirmative level of full development when all the soloists intonate, in unison and with confident assertion, the pugnacious and characteristic ARIES melody.
Once their pitch range is expanded to an extent that allows clear melodic expression, the tails of the electronic sounds gradually acquire a more and more reverberating oscillation. This gives a sense of the melody being painted into musical space with blobs – a magnificent effect. The supplementing of the trumpet timbre by these sounds is captivating here as well.
After the unison statement of the ARIES melody (with excursions into polyphony in between) the musical strands now stably unwind into polyphony again, yet maintain their just gained high level of energy. With this, we enter the BRIDGE after ARIES. The seamless transition to polyphony and its further intensification here is astounding. Eventually, the combined level of energy and no-holds-barred polyphony, which the music finally arrives at, strongly resembles that of the intense stream of music as heard in the first eight minutes of the opening section of the Wheel, CANCER. Thus, at the end of the Wheel the music of SIRIUS has arrived at a similar character as at the beginning of the Wheel (at least this holds for the Summer Version heard here).
The process of intensification which the music goes through, from the start of its re-awakening after the prolonged resting moment in the middle of ARIES to its full unfolding and, beyond that, to more and more unleashing of polyphonic energy throughout the BRIDGE after ARIES, is remarkable. It is a single process in its seamlessness and spans over an extraordinary length of time, a total of about 11 min., while going through a wide variety of stages. As such it is an imposing achievement.
Stockhausen has the capability and loves to compose such large-scale, unidirectional, completely unbroken architectural archs of tension which unfold over very long stretches of time. In this he rivals the greatest past masters in the art and in his own way carries the art into new territories and dimensions. Further examples of huge large-scale archs of unidirectional, unbroken tension in his music that come to my mind include some parts of HYMNEN, the entire long section POLYPHONY in INORI, extended stretches of HARLEKIN, a long wave unfolding in EVAS ERSTGEBURT from MONTAG aus LICHT, and in OKTOPHONIE the development of a flood of music from the start of the section SYNTHI-FOU to the end of the work (see my essay).
Back to SIRIUS – at the end of the BRIDGE after ARIES the bass sings with dramatic solemnity: "Friends, we stop the Wheel, North and South thank you for your open ears!", and after additional comments by bass and soprano the ANNUNCIATION follows.
"After the WHEEL, NORTH and SOUTH bid farewell on their own behalves (duet) and for EAST and WEST (duet), and the following message is announced as a quartet:
'...Only this period of creation has the virtue – still undiscernible for you – that in the entire eternal infinite it is the only one in which I, creator of all worlds, have completely taken on the nature of the human flesh.
I have chosen for Myself within the entire, immense Universe, this particular capsule, and within this, the local universe whose central sun is SIRIUS, and among the 200 million suns rotating around SIRIUS, I have chosen just your Earth where I would incarnate as human being...
Here I will raise, for all times and eternities to come, children completely similar to Me, who, together with Me, will reign over the entire infinite...' 1)
"1) Transmitted through Jakob Lorber, Der Kosmos in geistiger Schau, Lorber-Verlag, Bietigheim, 1961, page 90."
The message is carried beautifully by the bass in speechsong of dance-like agility; its melodic lines seem to remotely lean on the PISCES melody in an intriguing way. Simultaneously, in a sophisticated manner, this melody appears to be articulated in all its original elements by the sum of interactions of the melodic lines from all the four soloists, of which the line sung by the bass is one component of course. In the last part of the announced message the melody switches to AQUARIUS.
At the end of the message we hear the re-appearance of the engine noise of the mothership carrying the messengers from Sirius, a noise already known from the beginning of the work, while sustained notes from the soprano voice and the big and bright electronic percussive strikes returning from the beginning of the work continue the music and its tension for a while.
The work finishes as dramatically as it started, with the four messengers returning to the mothership with their smaller ships. The engines accelerate to high frequencies that are then held and fade away in volume, a process which is heard in a subsequent fashion for each one of the four ships. The roaring of the engine of the mothership, slowly fading away, brings the work to its conclusion.
From the simple collection of melodies in TIERKREIS (splendid as that is in itself) Stockhausen extracted the material to create in SIRIUS what must be one of his grandest musical statements and, as I believe, also one of his greatest.
SIRIUS is available on a 2-CD set from Stockhausen-Verlag (CD 26). The performance of all the soloists is of extraordinary quality. Boris Carmeli (bass) and Annette Merriweather (soprano) sing with impressive power and fullness of voice and with vivid expression throughout. Both the performances of Markus Stockhausen on trumpet and Suzanne Stephens on bass clarinet are a showcase of how to combine amazing musical fluidity and subtlety with great liveliness. The trumpet sounds with incisiveness of energy, when called for.
"[...] Also the rehearsals (in special rooms with 8-channel tape playback and microphone amplification), extending [...] over nearly 2 years, until the piece was completely learned, are phenomenal pioneer-accomplishments of the soloists. The exact synchronisation by means of earphones, without conductor, alone requires a completely new technique of hearing, singing and playing."
The recording is extraordinary as well. It sounds precise, colorful and dynamic, with great timbral accuracy, great quality of bass, high resolution and direct vividness. Though energetic sounding, the recording possesses no hardness of timbre at all, thus it can be played back at high levels (at or approaching those of a live performance) without giving the impression of any strain – provided your stereo is up to it.
Strongly recommended are also CDs containing the composition TIERKREIS that provides the melodies SIRIUS is composed of. They offer another, very direct opportunity of becoming intimately familiar with the melodic material. As far as single CDs go, TIERKREIS is available from Stockhausen-Verlag on CD 24 that features the version for music boxes which the melodies originally were composed for, and on CD 35 which contains the especially colorful Trio Version (3 players) for clarinet, flute and piccolo flute, trumpet and piano. The version for clarinet and piano is available on the 3-CD set CD 32.
Furthermore, for those who love SIRIUS and want to more deeply penetrate the composition, I recommend ARIES for trumpet and electronic music (Solo from SIRIUS) with a duration of 15 min. (on CD 33), and LIBRA for bass clarinet and electronic music with a duration of 32 min. (on CD 32; that music begins already in the middle of the section CANCER and continues through the entire section LIBRA of SIRIUS). In these musics, where only trumpet and bass clarinet, respectively, play together with the electronic music of SIRIUS, the listener can view the electronic music and the interaction of the soloists with it under a magnifying glass as it were, which is exciting. The booklet of CD 33 with ARIES also contains detailed and fascinating comments by the composer on the transformations in the electronic music.
© Albrecht Moritz 2002, text edited 2005
Performance update 2022
Addition 2005: Now the electronic music of SIRIUS can be heard on its own as well, on the CD 76 set.
Wikipedia page on SIRIUS
Stockhausen: Sounds in Space: Sirius, Aries, Libra, Capricorn