The fictive "collective unconscious" of the clarinet is probably like that of most instruments, at least at first. It "knows" various traditions: klezmer, classical, blues. And, among those traditions, it has rich inner life: it knows both the slow movement of Mozart's Clarinet Concerto and the raunchy opening glissando-lick from Gershwin's Rhapsody in Blue; it knows Benny Goodman and Bartók's Goodman, and it fathoms Brahms.
What does Helmut Lachenmann's clarinet know? Initially, nothing. In his notes for his 15-minute clarinet piece Dal Niente (1970), Lachenmann himself seems to suggest wanting to empty out the imaginary knowledge of instrument, as if to purge the object of all consciousness in some strange purifying move. The composer, with his own slightly infamous manner of formulating thoughts, speaks of relocating the "expressivity that was ousted from the single gesture to the emphatically concentrated experience of an awareness of [artificial structures'] anatomy." Or: the instrument, previously so full of semantic and expressive "knowledge" (of Mozart, of Goodman), suddenly becomes evacuated by compositional strictures which, through their rigor, allow the instrument to become "merely itself": a tube, through which air is blown in a fantastic variety of fashions.
In the process, however, an entirely different kind of expressivity reveals itself; Lachenmann calls Dal Niente "instrumental musique concrète," a music made of the sounds that can be found within the instrument's technology and means, rather than simply its intentional mode of exploitation. The resultant music, in one of Lachenmann's more famous phrases, is "sound as information about the conditions of its creation" -- that is, sound not as the attitude of Brahms, but of breath, or wood, or the weight of keys, or the pulse's effect on the lungs and the lips. Imagination infests the machine, around and against what it was told it could already find there.
Hence the majority of Dal Niente becomes a kind of sonic map of the clarinet itself, in its mythic "pre-consciousness": we hear vast stretches of pitchless blowing through the tube, meticulously graded in general frequency, dynamic, and articulation, seem to suggest silence as an ocean whose level is constantly in flux between tide and individual wave; occasionally pitch emerges, but less as a return to the traditional than as a kind of atavistic yawn, or scream. And of course there's the title-gesture, entirely endemic to the clarinet above all instruments -- the sound of sound itself, emerging from total silence, from nowhere.
But what makes this work (and other by Lachenmann) so magical is its suggestion, growing more and more palpable as the work progresses, that this "emptying out" of the instrument has actually unleashed something of tremendous power -- that indeed a great force lies within this little wooden pipe. One could call this effect, so common in Lachenmann's scores, enargeia, that Greek term which literally means "in-work": it seems an ideal word for the radiant sense of presence -- a presence with no name and no "knowledge" -- which gradually creeps into Dal Niente, and possesses the sound-scene.