All Jacoby's compositions except one string concerto were written in Israel. Jacoby arranged many songs for
Bracha Zefira, one of the pioneer female singers and songwriters of modern Israeli music, both songs written by herself and song she collected from others. These songs had a varied arrangements, from a classical
chamber ensemble to a
trumpet-only accompaniment. In the collection "Songs With Piano Accompaniment" (שירים בליווי פסנתר) he applied
Gregorian modes to Israeli folk music. He wrote the
cantata "A Day Will Come" (עוד יבוא יום) to a poem by the
Labor Zionist ideologue
A. D. Gordon. In 1946 he rewrote it as a string
suite, which he later again reworked for a whole orchestra. For this suite, titled "The Tiny Suite", he received the
Engel award in 1952. Yaakobi wrote three symphonies, in 1944, 1955 and 1960. The first one was first performed by the Israel Philharmonic Orchestra conducted by Yaakobi himself in 1946. The second was first performed in
Vienna and conducted by
Heinz Freudenthal. In 1948 the
Jerusalem Symphony Orchestra performed his overture based on the melody of the traditional
Hanukkah song
Ma'oz Tzur. He felt alienated from the developments in music of his time, and in the description to his work composition
Serio giocoso he wrote that he felt it important to write simple human music at a time when much of new music was too improvised, too intellectual or too electronic. In 1975, as a resident artist in the Technion, he wrote
Mutatio, a piece based on the traditional Rosh Hashanah chants of
Kurdish and
Iraqi Jews. == Bibliography ==