TELEMUSIK is without doubt one of my favorite Stockhausen works. The melding of synthetic tones with "ancient music" is an amazingly successful one, even without the ring-modulation as "lubricant". It's no surprise that many in the avant-garde crowd are also fans of "early music" - both are somewhat beyond our general listening experiences that they might as well come from other planets. The ritual music of Asia is especially appropriate since it's form mostly stays away from western classical "tonic-dominant" cadences and homophonic textures. In general, they're somewhat more modal in tonality and use heterophony as the main form structure. This actually has a very similar flavor to the manipulation of sine-wave bandwidth tones. Having said that, the ritual music is very modulated, so that on initial listens I didn't even know most of the time what was synthetic and what was "found sound". After spending some time exploring world music, these fragments are much more recognizable, and at that point Stockhausen's quote about finding an "apple on the moon" becomes much more appropriate. Another thing that strikes me as fascinating is that the "high band" layer of the RM'ed world music still has every element of the original but in a parallel "higher sphere". Like YLEM, this brings to mind the modern cosmological theory of "stacked" parallel universes.
It's interesting to compare this with Stockhausen's previous ring-modulation work, MIXTUR. There, Stockhausen processed melodic and rhythmic fragments and textures, so that the RM effect is audible when an instrument is playing. In TELEMUSIK, the samples are all rhythmic (steady and periodic) and have a generally even density. In this way, instead of creating a melodic figure with a trombone solo, faders and "solo" buttons are used to "play" isolated bits of the prerecorded music (for example, in Structure 1 channel III and IV).
I feel that it could be useful to have a discussion-forum on the music of Stockhausen. There are so many people from all over the world, young and old, learned and eager to get into contact with this musical world: musicologists, composers, musicians, music lovers; people who plan concerts - who write books or have to give lectures and so on. So there should be much stuff, many ideas that we can share. And when we have open questions, there may be people who studied just that and could give a hint or a stimulus.
A problem might be the English language, but i feel that is the only possibility that many people who are interested can participate. And we can exercise tolerance to mistakes!