Grosz initially learned to play the violin with Marc Benador, at the age of 5, before switching to the viola at age 11. In Jerusalem, he was taught by David Chen, later by Tabea Zimmermann in Frankfurt and Berlin as well as in Tel Aviv with Haim Taub, who had a formative influence on him.
Grosz was a founding member of the Jerusalem Quartet in 1996, and played with them until 2009. During his time with the Quartet, they received a contract with the label Harmonia Mundi. A number[clarification needed] of their recordings have been awarded prizes such as the BBC Music Magazine Chamber Award or the ECHO Classic Award 2009.
In 1996 Grosz won first prize at the Brown-Roger Siegel Competition and in 2007 he received the Gottesman Prize for viola at the Aviv Competition. In 2004, Grosz performed the world premiere of Omer Meir Wellber’s Viola Concerto.
Grosz has played with Daniel Barenboim’s West-Eastern Divan Orchestra and the Jerusalem Symphony Orchestra. Grosz has also collaborated, in solo and in chamber music projects, with artists such as Yefim Bronfman, Emmanuel Pahud, Mitsuko Uchida, Oleg Maisenberg, Janine Jansen, Julian Rachlin and David Geringas; he performs regularly in concert halls and festivals such as the Delft Festival, Salon Festival and Verbier Festival, BBC Proms, Bahnhof Rolandseck, Utrecht International Chamber Music Festival, Spectrum Concerts Berlin and West Cork Chamber Music Festival, as well as the Jerusalem Chamber Music Festival, founded by Elena Bashkirova in 2009. In 2012 Grosz performed Luciano Berio’s "Sequenza VI", for viola solo at the Philharmonie Berlin. In 2013 Grosz played as a soloist in Hector Berlioz's “Harold en Italie” conducted by Emanuel Krivine as part of the Berlioz Festival in France. Grosz plays a 1570 Gaspar-da-Salo viola.
- "Amihai Grosz, 1st Principal Viola (Berliner Philharmoniker)". Retrieved July 8, 2014.
- "Harmonia Mundi". Retrieved 8 July 2014.
- "Conductor Semyon Bychkov awarded Disc of the Year for Wagner's Opera Lohengrin". Retrieved 8 July 2014.
- "The Aviv Competitions 2008; Israeli Competitions for Young Musicians: 10th Year" (PDF). Retrieved 15 August 2014.