Atonality, as a replacement for tonality, I consider to be a failed experiment for the most part. Today for someone to criticize music as atonal seems rather archaic. It’s not that composers are writing more music that is tonal or atonal (though some indeed are doing so), but it is more that composers are just no longer very interested in that sort of organizational manipulation. Composers organize their music, of course, but not in the same way as composers writing in the great age of tonal music, or atonal music for that matter. In general, music today seems less linear and more environmental. Composers still tell stories, but it is usually done more as background music rather than with an interaction of musical characters.
Tonality developed at the beginning of the Baroque Period in response to the need for a way to organize instrumental music. Until then, written music was primarily vocal and was organized around the text. Though Renaissance music was tonal “sounding,” its sense of key (and musical structure) was entirely based on the emotional (and sometimes literal) impact of the text. Baroque composers writing instrumental music decided, with no words to fall back on, to make the music about the key and gradually developed a large interrelated structure of key relationships. Then they also borrowed from Classical Rhetoric and created “musical subjects” upon which they could expound.
Though the Rhetorical characteristic has remained nearly to the present day, the tonal aspect was challenged early in the 1900’s and remained a source of contention among not just composers, but all musicians. Though composers were at first interested in finding a replacement for the system of tonality, gradually the approach to pitch became just another original aspect of how an individual composer would organize his or her music. Often the approach would vary from piece to piece by the same composer.
But still, the way we listen to notes and their relationship to each other has not changed much, even if composers are using and organizing them in different ways. I believe it is possible to treat pitches as sounds, in the same way you would write for a percussion ensemble, for instance. But the composer must be careful to keep the pitches identified as individual units, which is not easy. The (pitched) music of Edgard Varése is probably the best example of this that I can think of, but still, you hear a (tonal) relationship between the pitches he uses, even if they are treated as static sounds. I don’t think you can change the way people hear the relationship between the notes themselves.
Serialism, music using the twelve-tone method, tried to organize music in a different way. It tried to replace a tonal relationship with one based on order. I have no problem with the effort; I just don’t think it worked. It was a very versatile technique, and fed directly into the creative imagination of several composers, but it now seems rather dated. Its problem was that it was, at best, only barely detectible in the music. Because you couldn’t hear the ordered relationships of twelve-tone rows, you tried to hear the music the way you normally would. Listeners still try to hear tonal relationships. If the method was more obvious that might not be the case, but it just isn’t. You can take tonality out of the music, however, you can’t take it out of the listener.
In many pieces, serialism seems to neutralize tonal relationships with speed. The composer seems to circulate through the twelve tones so quickly as to cause the listener to experience tonal vertigo. I think it is this overloaded tonal dizziness that most listeners associate with atonality. It is like a cat in a speeding car; he is born to detect motion, but the whole world is moving!
An interesting and somewhat quaint description of tonality and serialism appears in The Book of Laughter and Forgetting, by the Czech author Milan Kundera. A character in the story, who happens to be a pianist, relates how his father had taught him tonality. The tonic was the king, and the dominant and subdominant are his right-hand men. All the other notes were members of the court, and each had its own relationship to the king. But each note also had its own court, with its own relationships. A composition, therefore, was a drama played out among all these players with intrigue and romance, and even occasionally the threat of treason. He then goes on to criticize twelve-tone music as being like Socialism by trying, and not succeeding, to make everybody the same. Kundera was not a big fan of Socialism.
It’s my opinion that one of serialism’s fatal flaws is its blind acceptance of enharmonic equal temperament as truth. Declaring all F#’s and Gb’s as identical severely restricts the variety and scope of tonal possibilities available. It also clearly ignores how Western ears hear tonal color.
Even on an equal-tempered piano, we hear pitches as being a sharp or flat based on the context in which they appear. This is often demonstrated melodically (C# moves to D, Db moves to C, etc.), but is also true harmonically. If you play the two chords below, alternating back and forth, the F# and the Gb are clearly different notes, even though they are exactly the same frequency!
The first chord opens outward as the resonance and surrounding notes create a clear F#. In the second chord, however, the Bb and Eb clearly redefine the target note as a Gb, which seems to contract back toward the same C major chord in the left hand, creating a completely different effect.
Even though the pitch is the same, how we perceive the pitch is different because of the surrounding environment. Most atonal writing either ignores this, or tries to neutralize it by making the music so dissonant that the relationships are of little consequence. Making tonal relationships moot can be very effective, in, for instance, the early music of György Ligeti or Krzysztof Penderecki. But writing tonal relationships and then ignoring them is a questionable compositional practice that promotes listener confusion and frustration. It is a practice that a composer uses at his own peril.