Twelve-Tone Composition
johndcook.com
johndcook.com
Unfortunately it also made listening to music a purely intellectual exercise as well, and a painful one for folks who expect tonality to be a part of any music they want to sit through.
Thankfully folks like Steve Reich, Terry Riley, and Philip Glass came along to embrace the rigid structure and intellectual design approach, but to return tonality as a core principle with Minimalism. Art Music was listenable again.
Especially Bartok’s late works are more approachable (Concerto for Orchestra, Piano Concerto no. 3) and while they don’t slam home a tonal key like the end of Beethoven’s Fifth, the harmonies are plenty recognizable.
In many ways atonality was the inevitable direction that late 19th century Romanticism was moving in, with increasingly ambiguous tonality expressed by composers like Wagner and Mahler. In the early 20th century there was an explosion of new approaches and techniques which started from this basis and pushed tonal approaches to the breaking point and beyond. Composers including Ives, Stravinsky, Schoenberg, and others were all trying new things within the realm of atonality and while we tend to look back and map history into narrow movements and philosophies to suit our current thinking, I don't think there was necessarily such a "serialism period" so much as there was the Second Viennese school along with a bunch of other composers trying things out at the same time. And even within the Second Viennese school the approaches were distinct; Berg is known for being a bit more "loose" and romantic in his usage of 12-tone technique vs. the rigid formalist Webern.
Leaving aside the dubious assertions of what is or is not listenable, the reality is that art music in the 20th century became more and more fragmented as the entire music scene changed around the world. Minimalism was just one thing that happened after serialism. Even if we exclusively focus on music labeled "European Art Music" the 20th century was a period of incredible experimentation and exploration with many different approaches to tonality (and atonality) introduced.
however much atonality and other formalisms represented an intellectual inevitability, they also are ultimately useful mostly for having mapped a good bit of the coastline defining where the experience and enjoyment of musicality is grounded in ways which are obviously embedded in both physics and our particular embodiment, and to lesser degree, culture.
Jazz did a much more nuanced mapping of that ground IMO, but to the same end result: beyond the coast there is deep water, and there we do not swim.
Nor shall we, the collective. Not so long as we live in these bodies.
Individuals can swim; individuals can endeavor or through some rare combination of circumstance find musical value and enjoyment in the water, i.e. beyond conventional melody harmony and rhythm...
...but no amount of intellectual scaffolding or historical cultural momentum can bridge it.
Humans cluster inland.
I've spend decades in the experimental sound/music community and mapped some largely unvisited coves myself, having a particular interest in what in those intellectual traditions was called musique concrete;
and been to countless "noise" shows, and lived through many generations now of enthusiastic "kids" rediscovering various aesthetics.
The lines don't budge. The cultural framing of what it means to transgress them, and the communities that form around celebration of that "transgression," are all unique in their specific concerns, and—unhappy in the same way.
Minimalism was a welcome success for pretty obvious reasons: it was a reversion and embrace of exactly those things at the heart of our embodied experience of music.
Each person usually has a different "algorithm" and explain how they came up with the riff or song. It can sound quite evil.
The word I've heard for this is Dodecaphony.
Here is an example of one: https://www.youtube.com/watch?v=wCL3E0Mh4js
12-tone serial music always sounds to me like it belongs in a film soundtrack — it works well as background because the serial method suppresses the creation of recognizable melody as a foreground element.