In his student years he served as conductor of the Voronezh Philharmonic Orchestra and performed with the Big Concert Orchestra at the Hall of Columns (in The House of Unions) and in studios of State Broadcasting and Recording House.
In 1993, thanks to recommendation and personal artistic support of composer T. Khrennikov, he became a Chief Conductor of the Lipetsk Symphony Orchestra; and in 1997 he was nominated as conductor of the Svetlanov's Russian State Symphony Orchestra. With this prominent ensemble Sidnev worked and gave concerts in Moscow and on tour in Russia and abroad.
Since 1999 Sidnev began teaching at the Moscow P. Tchaikovsky Conservatory and to conduct productions at its opera studio. In 2000-2001 he was the Music Director of the Moscow Youth Symphony Orchestra "The Future of Russia" and conductor of the Moscow tour opera company "NOTE" which cooperated with the Russian leading opera theatres and outstanding vocal soloists. Since 2008 he has been an Assistant Conductor of the renowned Moscow State Symphony Orchestra (Music Director Pavel Kogan).
Sidnev regularly participates as a guest conductor in concerts of music festivals in Russia and CIS, as well as in monographic evenings dedicated to A. Arensky, S. Vasilenko, A. Glazunov, A. Scriabin, S. Rachmaninov, T. Khrennikov, K. Khachaturian Y. Svetlanov, and others.
In a number of theaters in the country he staged operas and ballets by Borodin, Dargomyzhsky, Rachmaninov, Rimsky-Korsakov, Tchaikovsky, Gounod, Verdi, Puccini, Leoncavallo, Delibes. He presented the audience a wide variety of symphonic and chamber music programs, including those which are rarely performed and unfairly neglected.
A wide repertoire of A. Sidnev includes all the major compositions of national and world symphony, opera, ballet and chamber music.