For a band that was so interested in breaking musical stereotypes and pushing against the norm, it's strange that Ralf Hutter and Florian Schneider - the core members of Kraftwerk - would essentially treat the band's first few releases as if they simply don't exist.
This is incredibly odd when it comes to Kraftwerk 2, the group's sophomore release. Stripped away are the synthesizers that would become their trademark, and true musical experimentation (with the liberal use of tape loops) becomes the norm here. And, the thing is... it's fascinating as hell.
When you find yourself locked into nearly second of the 17:36 of "Klingklang" wondering just how the hell they make simple progressions sound so amazing, you know that Hutter and Schneider had achieved their goals. Yes, it's not always music in the strictest sense of the definition; there are enough subtle nods to such composers as Varese and Stockhausen, but quickly becomes their own unique product. Similarly, "Spule 4" sounds like experimentation with guitar and bass - it's akin to putting me in a room with a Stratocaster and a series of effects pedals. Yeah, we're not talking top 40 material here... but it's strangely hypnotic. 
And it is in the experimentation where Kraftwerk 2 achieves its greatest success. For Hutter and Schneider, the end result did not seem to be the overall achievement; it was finding ways to create and shape the basic instrumentation into something completely unexpected. "Spule 4," for example, grabs the listener with what sounds like a bass guitar riff, and refuses to let go for nearly 10 minutes... leaving the listener wanting more. Even "Harmonika," simply tape manipulations of the humble instrument in question, is beautiful in its simplicity - almost as if you're listening to someone near the end of their life pouring their being into slowly playing a harmonica with controlled, labored breathing.
If I have any criticism about "Klingklang," it's in the speed manipulation of the tape loops. Truthfully, I found myself getting into the rhythmic patterns of the song, only to have to adjust my own experience as things got faster or slower. I understand that this was part of the experimental process, and I accept that; doesn't mean a boy can't wish for something.
I get it; there are people who will hear tracks like "Atem" (which is simply effect-laden breathing) and "Wellenlange", scratch their heads in confusion, and wonder just what the hell they listened to. And, admittedly, Kraftwerk is not necessarily a band you're going to get after just one cursory listen. But if you take the time and listen to the layers of sound that make up the six tracks on this album, you'll find there's an absolute treasure trove waiting to be discovered.
Hutter and the late Schneider have spent the bulk of their career trying to downplay albums like Kraftwerk 2 out of existence. They made a grave mistake in trying to do so with this album. It is one of the most successful experimentations in simplifying music down to its most basic elements, and is oen of the most fascinating things I've heard in a long time. I strongly doubt that Hutter will read this, but if he does, I respectfully ask him to consider re-releasing this officially.