I'm always skeptical when I see an acoustic/electronic collaboration because I tend to think the acoustic instrument sounds so old-fashioned compared to the sonic wizardry of electronic composers. Some composers really do it right. Stockhausen, Cage, and many others have given us some amazing electro-acoustic work over the years, but I've heard just as many works that feel like, say, marimba with a techno beat in the background. That is not the case here. Somehow Sakamoto and Noto managed to create an absolutely amazing balance, to the point that the listeners completely forgets that he or she is listening to two very different instruments.
Sakamoto's mournful piano work gently floats over the top of Noto's abstract electronic sounds making their strangeness accessible enough for almost any listener. I wouldn't normally recommend an Alva Noto CD to most people - his style is so difficult that many are just going to be turned off. Again, that's not the case here. The harmonic and melodic content of the piano, sparse as it may be, makes the experimentalism palatable enough for anyone.
Noto and Sakamoto have worked together previously on "Vrioon" and later on "Revep", but I'm not sure I could pick a favorite album. They are certainly different, and I suppose the majority of the decision will hinge on what you happen to like. "Vrioon" seems to feature less piano and more electronics. "Insen" has more-or-less constant piano, whereas there are long stretches of electronic foundation in "Vrioon" with only momentary punctuation from the piano. I don't own "Revep", so I won't rely on my memory and risk a faulty assessment. I will, however, assure you that it's equally lovely and quite worth your time.
I can't find a fault with this album. It's deep and thought-provoking, with plenty of detail to discover over multiple listenings, but at the same time, it's strikingly beautiful and haunting. It practically forces the listener to become lost inside its enveloping textures.
I highly highly recommend this disc to fans of non-dance electronic music, or to new music aficionados in general. This is an album you'll return to again and again.