9) is a collection of concertos by the Italian composer Tomaso Albinoni, published in 1722.
The most famous piece from Albinoni's Opus 9 is the Concerto in D minor for oboe (Opus 9, Number 2).
This concerto is probably the second best-known work of Albinoni after the Adagio in G minor (which was once believed to be a reconstruction based on a fragment by Albinoni).
The concertos were dedicated to Maximilian II Emanuel, Elector of Bavaria, and were first published by Michel-Charles Le Cène in Amsterdam.
[1] It is possible, but not certain, that they were written in the Elector's court during a 1722 visit there by Albinoni during performances of his theatrical compositions.