Fidelio of overwhelming the (rather light) initial scenes of the opera. Beethoven accordingly experimented with cutting it back somewhat, for a planned 1808 performance in Prague; this is believed to be the version now called "Leonore No. 1". Finally, for the 1814 revival Beethoven began anew, and with fresh musical material wrote what we now know as the "Fidelio" overture. As this somewhat lighter overture seems to work best of the four as a start to the opera, Beethoven's final intentions are generally respected in contemporary productions. While some believe that Gustav Mahler introduced the practice of performing "Leonore No. 3"
Fidelio to be broadcast in the USA, over the NBC radio network, in December 1944, by the NBC Symphony Orchestra, featuring soloists from the Metropolitan Opera (though a shortwave broadcast of one act, conducted by Toscanini, had earlier been relayed from a 16 August 1936 performance at Salzburg.) Divided into two consecutive broadcasts, the 1944 performances were later issued by RCA Victor on LPs and CDs. "Fidelio" was the first opera performed in Berlin after the end of the World War II, with the Deutsche Oper staging it under the baton of Robert Heger at the only undamaged theatre, the Theater