With listening to (classical) music one can get caught in what I shall call “an obsession with the right notes”. Are the notes - when they come to you in a not so familiair harmonic language - played correctly? Is there any kind of structure in this mayhem I'm hearing? A significant part of how you are going to appreciate (or not) a piece of music can depend on the (positive) answer to these questions because you don't want to feel cheated or lost. There can be a need for wanting to rely on the composer's integrity if the structure of a piece seems determined to hide itself. And that need can be most persistent.
There is this video clip on YouTube. It shows Maurizio Pollini playing a piece for piano by Stockhausen. Pollini is counting. You see his jaw going up and down, like he is whispering. I have never seen him do that in Beethoven or Chopin. It's like the notes in Klavierstücke IX don't reveal their connection when he is playing them. He has to secure the relation between the notes by counting. To prevent that they will become islands. Entire of themselves.
During the 75 minutes of Mantra, there are a lot of things going on in which one can search, with futile efforts, for some points of reference. I, clean washed by the heavy metal therapy in the days prior, thinking more in sonic colors than in contrapuntal finesse, just let it happen. It's not that the mind, always looking for some kind of inner logic, isn't completely left to it but it took some time before the structure of the piece started to show glimpses of itself. It's as if the music is constructed with very specific ideas about sound in mind, more than it shows itself as the next logical step after Schönberg and the Second Vienna School. More like hip hop – with its samples based on colors of sound – than like traditional pop music – with its instruments tuned in a certain key. But as far as music theory goes, I have to admit that I lack expertise to back that comparison up.
There is a bigger gap between Stockhausen's Mantra and a Haydn sonata than between the former and a metal song
The dialogue between pianos in Mantra is not without humor. It even stretches that humor a bit by times – like a joke that it's told a few times too many. After one hour (around 1.03.25 in the video below) the music turns into some kind of Boogie Woogie-on-steroids that feels like a perpetuum mobile (be it only for a few minutes). It's the zenith of a piece of music that I receive with some proper back-and-forth movements of the head. Mantra from Karlheinz Stockhausen is caffeine for the brain that generates energy not unlike that of a rock concert. I say "Hell yeah!" to that.