Vojtěch Matyáš Jírovec (Adalbert Gyrowetz) (20 February 1763 – 19 March 1850) was a Bohemian composer. He mainly wrote instrumental works, with a great production of string quartets and symphonies; his operas and singspiele numbered more than 30, including Semiramide (1791), Der Augenarzt (1811), and Robert, oder Die Prüfung (1815).
Gyrowetz was born 20 February 1763 in České Budějovice (Budweis). His father was the choirmaster in the cathedral there, and Adalbert first studied with him. He then travelled to Prague, where he studied law but continued to learn music.
At around this time Gyrowetz was in the employ of Count Franz von Fünfkirchen in Brno, whose employees were all musicians. Here he started composing (among other things) symphonies, of which he was eventually to write more than 60. In 1785 he moved to Vienna and met Wolfgang Amadeus Mozart, who performed one of Gyrowetz's symphonies in the same year. From 1786 to around 1793, he travelled throughout Europe. He spent some time in Paris, where he established that some symphonies that had been published as the work of Joseph Haydn were in fact his work. He spent three years in Italy, meeting Johann Wolfgang von Goethe in Rome and studying with Nicola Sala in Naples. In 1791 he met Haydn, whom he idolized, in London. While in London, he was commissioned by Johann Peter Salomon to compose symphonies to be performed at Salomon's Hanover Square Rooms concerts.
Gyrowetz moved back to Vienna and in 1804 was appointed Vice-kapellmeister of the Court Theatre. Gyrowetz was an important part of Viennese musical society well into the 1820s and even arranged the piano reduction of Rossini's Zelmira in 1822. He was one of the pallbearers at Beethoven's funeral in 1827. Gyrowetz died 19 March 1850 in Vienna.