Music sack gives two composers with this name, both Swiss. The other 's dates are 1842-1914. One composer's Op.1 is Berceuse pub 1889, the other's is 4 Lieder pub 1901.
The earlier Oskar Kahl was the leader of the Zurich Tohalle orchestra in 1870. He was a friend and brother in law of
Georg Wilhelm Rauchenecker (1844—1906). He was a distinguished chamber musician, for example leading from 31 December 1870, a series of 7 quartet evenings at the Wagners’ house, with Rauchenecker (2nd violin), Hans Richter (viola) und Hermann Ruhoff (cello) rehearsing string quartets by Beethoven.
His place in history is assured by his participation in the first European performance of Brahms' sextet Op.36 on 20th November 1866, in the large hall of the Kasino in Zürich, along with Friedrich Hegar, Nordmann, Geisser, Spiegel and Kriebel