After the films changed to sound, Walt Disney began making Mickey Mouse and musical "Silly Symphony" shorts. To keep costs down Disney produced his own music. Disney's first music director and composer was Carl Stalling. The Mickey Mouse shorts used pop music while the Silly Symphony cartoons used Classical music. In 1932 the studio produced its first cartoon in Technicolor, "Flowers and Trees". The success of the song Who's Afraid of the Big Bad Wolf?, from the Silly Symphony short "Three Little Pigs" (1933), convinced Disney to keep producing original music. It was at this time Disney introduced the characters of Donald Duck, Goofy, Pluto and Minnie Mouse. Over its ten year run, "Silly Symphonies" had won Walt Disney the Academy Award for Best Animated Short Film seven times. This record was matched only by "Tom and Jerry". The series spawned numerous imitators and competitors. United StatesFebruary 29, 1929 BrazilDecember 25, 1929 United KingdomJuly 21, 1930 UruguaySeptember 11, 1930 MexicoDecember 25, 1931 PortugalMarch 16, 1932 IrelandApril 3, 1932 GreeceApril 10, 1933 SwedenOctober 7, 1933- Argentinian in Chilean SpanishDecember 11, 1934