Metamorphosis, for trombone octet, is a piece where the themes constantly change and transform into something new. In its slow beginning, a lyrical melody is played against a drone until it’s joined by more trombones. This happens three times. Then, the entire choir is joined together to form the climax to the slow section before the transition to the faster section.
Almost instantly, the mood changes into a more playful sounding section.A new bouncier theme is introduced against muted eighth note chords in the background. In its second big statement, the presentation of the theme is broken up with different motives from both the beginning slow section and the fast playful theme. In its third statement, only the smaller motivic ideas are left as the volume and intensity grow.
Finally, both melodies get squished together. The initial lyrical melody is once again stated, but this time it’s over the background of the second playful melody.