Keller, Max E. (b. March 19, 1947, Aarau). Swiss composer of mostly stage, orchestral, chamber, vocal, piano, and electroacoustic works that have been performed throughout Europe and elsewhere; he is also active as a pianist.
Mr. Keller studied composition with Nicolaus A. Huber, Thomas Kessler, Helmut Lachenmann, and Hans Ulrich Lehmann, as well as German, history and musicology, on a scholarship from the Heinrich-Strobel-Stiftung.
As a pianist, he played free jazz and improvised music from 1966-73, featuring the piano and electric instruments, and has again worked as an improvisational musician since 1985, most notably with Trio Ampio. - composers21.com

From liner notes:
Mimi no Ho - The 17 pipes of shô (Japanese mouth organ) are not ordered in pitch. The performer senses the positions of his index finger while playing. It is possible to build movement patterns based upon the proprioception and the kinesthetic feeling. Viola has no frets. It is possible to slide not only a single pitch but also the whole melody line on the fingerboard. This piece is composed with the above observations of the playing methods.

A pupil of Yehudi Menuhin plays 15 pieces by 15 composers in 20th century as a Tribute to the mentor. Although the order of tracks could have been a bit better organised, the recording will allow us to reconfirm that contemporary music does not stand for being ostentatious.

Profound and tender aspects within Rituel - In memoriam Bruno Maderna have been successfully realized in this recording - no less than that by the composer Boulez. The orchestral work by Lachenmann may as well be catchy thanks to the performers.

Quite a few will agree that Japan's experimental rock/jazz musicians enjoyed their affairs best in early 1990's. Such technological instruments as electronics and turntables are more of ways of free (in terms of ideas) improvisation than of acoustic effects, which I believe is their characteristics.

Recorded live in April 1980, Tokyo. I must confess that I decided to share this one in spite of my pathetic internet connection since it could be a valuable source on Irvine Arditti no more than a couple of months before his 'graduation'.
The performance in this live is of course of good quality, though some rough brass playing is recognised in the opening of Mussorgsky.