It opens with a scream and ends in a hymn. Jonathan Harvey's orchestral work, Speakings, is possibly one of the most adventurous orchestral compositions ever undertaken by any composer, certainly in the recent history of music.
It is almost outrageous in what it strives to depict and achieve. Even the gentle, wise and soft-spoken Harvey, among the most respected and revered of British composers, and a man given wholly to understatement, considers that Speakings is "the most complicated and ambitious composition I have ever written".
The piece is part of a triptych of compositions written by Harvey for the SSO during his tenure as composer-in-association to the orchestra. It was premiered last summer in the Royal Albert Hall during the BBC Proms. Ilan Volkov and the BBC SSO gave the performance, aided and abetted by a team of computer designers and sound engineers.
Those same forces will give the first Scottish performance of Speakings tomorrow night in the City Hall, Glasgow, an auditorium that will be sonically enhanced by a bank of six loudspeakers transmitting live orchestral music, some of which will be transformed, as it is played, by treatment from custom-designed computer programmes.
The effects, which will be both spatial and sonic, are bewitching, beguiling and possibly baffling to an audience that will hear instruments with different characteristics than they normally possess, and voices that appear to be speaking, though not necessarily articulating in a conventional manner.
Sounds bizarre? Scary? Forbidding? Intimidating? Possibly, but only because the super-sophisticated orchestral music circulating around the City Hall will not have the regular, familiar accents of classical music, even contemporary classical music.
I put it to the composer that, for an audience, it is useful, if not essential, that they have some sort of basic guide, or sense of navigation through the piece, in order to make it approachable. He agreed, so I made my own "big picture" analysis and discussed it with him. He approved the perception. So here it is.
Speakings is about language. It's a big piece of about 25 minutes. There are three sections but the music runs continuously and you will probably not hear the joins.
The music has three distinct stages. The first is the birth of language, a kind of introduction lasting about three or four minutes. The second is about the development and evolution of language, which occupies the long central section of the piece, for about 15 minutes. And the third is about the establishment of language.
Harvey is fascinated by the evolution of language both historically and its development in the life cycle of human beings, from our first sound - a scream or a cry - which is how Speakings opens, through our struggle and development towards exercising language, expressing emotions and communicating, which is the animated central section of the piece, to the point where language is established and can be used to form a coherent expression, represented in Speakings by the arrival of an identifiable theme, here in the form of a plainchant-like hymn or mantra.
"I've long been fascinated by the relationship between speech and song. I imagined a journey of growth, arriving at song, but in a different way, one that made the connection with speech rather more clear.
"I then imagined the orchestra going through this process, wanting to speak, struggling to speak, to utter, which, of course, they can't, though they get near it."
How to get the orchestra closer to that form of expression set Harvey off on the chase, albeit a scientific one. "I fed recordings of babies into the computer, which analysed them very precisely in their pitch, timbre and the harmonics occurring in a baby sound. I could then transport all that into orchestration."
Even then, of course, the orchestra would still sound like an orchestra, in other words an orthodox musical instrument and a mere approximation; and by this time Harvey was on the trail of an orchestral sound that could get closer to, and be influenced by, the actual characteristics of speech.
The answer had to lie in computers and electronics, so at that point he went off to Paris, to his second spiritual home, Ircam (Institut de Recherche et Coordination Acoustique/Musique), the elite research centre founded by Pierre Boulez, with which Harvey has been associated for many decades.
"I came to them with the idea of a speaking orchestra. At first they didn't know what I was talking about."
But there is a big department in Ircam specialising in the study of speech. "They simulate it in many ways, and there are many commercial applications of their work."
Existing programmes didn't fit Harvey's requirements, so, Ircam being Ircam, the computer designers thought out of the box, and a technique began to emerge. "They have just perfected it; it is completely new, totally original, works really well and is very exciting."
It all sounds high-flown and cerebral, but the new development is based essentially on the acoustic structure of the voice, which changes very fast, says Harvey. "In the voice you can have up to 10 different sounds per second, which, incidentally, is much faster than music."
The technique the Ircam designers have developed they call Shape Vocoding. Basically, it's a filtering process, with music being fed into the computer through one input, and speech, with its more rapidly changing shapes, being fed into another. The two are married, with the faster speech shapes the dominant partner, as it were. Ergo, if the engineers get the balance right, you can hear the sound of, say, an oboe playing which will uncannily appear to have adopted some of the characteristics of a voice, or at least a mouth. And a weirdly expressive and unsettling experience it can be, when it comes off.
Heavy-going stuff? Definitely. But the whole process is in the hands of a masterly and sensitive orchestrator, and Harvey has produced a superb orchestral piece, with passages of great excitement, unearthly beauty and a strange kind of transcendent quality.
What does he want an audience to take from Speakings? "I think it's a kind of parable of life. It's about the process of growing, of evolution; it's a process of living, of talking and of language.
"With the big central movement, I wanted a big picture of human life, a kind of scherzo with people arguing crazily, sometimes a bit sad. I just want that rich pattern of life to come across in this journey."
The whole operation will be live in the City Hall, with one of the Ircam engineers in charge of the computer input, Harvey in charge of balancing the output and conductor Ilan Volkov landed with the fiercely difficult role of combining and co-ordinating live orchestral music with live computer and electronic music.
Theoretically, they could input the entire orchestral sound into the computer. In practice, there will be a group of 11 orchestral players, with close mikes fixed to their instruments, whose music will be shape-vocoded, to coin a phrase.
So where does Jonathan Harvey, working somewhere beyond the front line of musical development, go from here? "To a very different work, but a very big one." Sir Simon Rattle has asked Harvey to write a vast 90-minute oratorio for the Berlin Philharmonic, the 70-strong Radio Choir, and a children's choir. The subject? "Global ethics," says Harvey, with a wry smile. Not a lot of that about today, I suggest. "I think its time has come," says Harvey. "It's an idea that appealed to Simon very much."
The work has been inspired by Hans Kung, the controversial Catholic theologian, "a real ecumenist". It will be a big piece, "a sacred piece, but in an ethical sense, and will be very inclusive, with one movement on Islam and another on Judaism". Harvey will be fully engaged on that commission for the next year. Jonathan Harvey's Speakings: Scottish premiere, City Hall, Glasgow, tomorrow, 7.30pm.