"MACH" (DO) is the title of a cycle of pieces for solo instruments which Eres Holz began in 2011 and which now comprises nine pieces. MACH! is both an exhortation and an homage to the physicist Ernst Mach. The unit of measurement named after him is used to indicate the speed of supersonic aircraft - an indication of the difficulty of the pieces. "MACH" for organ, as well as for harp, violoncello and accordion, the latter in each case with live electronics, can be found on the first CD of this double album.

The second CD is dedicated to chamber and ensemble music, whereby the string quartet "Dunkle Risse" (Dark Fissures) has autobiographical references, as does the titular "Touching Universes and Ends". Eres Holz' intensive preoccupation with the phenomenon of harmonics, especially including microtonality, characterises the quintet "Schakalkopf" as well as the only vocal work in the programme, "Die Frau".

"Alongside Sarah Nemtsov, Eres Holz contributed an outstanding work to this rich, thought-provoking forum. His string quartet 'Dunkle Risse' wants to set the negative pole to our society that only presents the positive. Beauty arises here from pain, from carefully developed, fragile sound spaces that are repeatedly broken open, in which the transience of sound leads us straight to the paradise meadow." - Neue Zeitschrift fr Musik, April 2022