"… His conspiciously highly developed personal style is based upon careful listening. The audible influences of John Cage and Morton Feldman on the spiritual side and Helmut Lachenmann and Mathias Spahlinger on the material level -although one can scarcely separate the two- oblige many of his pieces to the aesthetics of silence, to the refusal of tumultuous mental and constructional concepts. Their effect calls for a change in perception. In their best moments, the compositions themselves even assist in achieving this … but Walter's pieces, which sometimes last only a few seconds, do not necessarily live from a narration, or a process, but from a gesture, which is, as a rule, formed in a completely logical manner and which is as open as it is closed. Caspar Johannes Walter's imaginative use of the instruments' scraping, scratching and stroking sounds is never violent, but always conveys respect for the instrument …" - Ute Schalz Laurenze, Bremer Weserkurier, 20.4.94
"… And now imagine that in the current historical situation, in which no comprehensive musical language can be resorted to, indeed, not even any valid tonal system, a composer is commissioned to write a new string quintet under the sole condition that the premier should be coupled with a performance of the uncomparable Schubert Quintet. Caspar Johannes Walter took up Harry Vogt's (West German Radio) challenge with thoroughness, deliberateness and, above all, one may say that he succeeded. He calls his work »The End of a Story« -and, as far as its relationship to Schubert is concerned, the differences are glaring and the similiarities are deep and subtle. Belonging to the first category are: complex rhythmical structures, the interruption of a world of noises into tonal sequences, condensed time, the second, however, includes the contrary of all this: namely, generous periodic formations, predominance of the tonal art, long unbroken melodic streams of sound. Here, too, it is Walter's specificity that unites the differences and smooths the contradictions, namely his ability to establish a syntax, which exists nowhere else, into small musical cells which one can find nearly everywhere in contemporary compositions …" - Heinz-Klaus Metzger, Frankfurter Rundschau, 4.6.96