For this study, five hypotheses were formulated stating that ability to identify melodic intervals during music dictation is not affected by (1) the differences in timbre, (2) the use of familiar or unfamiliar timbres (MAJOR), (3) formal ear training experience (FETE), or (4) playing/performing experience on an instrument (PPEM), and (5) that there is no significant interaction between PPEM and FETE. Two hundred and twenty college and university subjects were tested, using an author written test of melodic interval identification. Melodic intervals were presented in random order by six instruments: clarinet, trumpet, piano, violin, xylophone, and synthesizer (sine waveform). Each instrument played 12 randomly assorted melodic intervals, based on C4 and not exceeding one octave. Results showed that FETE, PPEM, and MAJOR all affected subjects' scores on intervals presented with different timbres. There was no significant interaction between PPEM and FETE. (Author/RM)