In "Tiger Rag" by the Original Dixieland Jazz Band, what musical 'trick' occurs at about 30 seconds?

In "Tiger Rag" by the Original Dixieland Jazz Band, the musical 'trick' that occurs around 30 seconds into the piece is stop-time. This technique involves a sudden halt in the regular rhythm or tempo, allowing individual instruments to play brief, punctuated phrases typically accompanied by a strong rhythmic background layer. This creates a jazzy, lively effect where the ensemble can showcase their improvisatory skills while still maintaining the tight rhythmic structure of the piece.

Stop-time is particularly effective in jazz as it heightens the contrast between the rhythmic sections and allows the performers to play off each other's spontaneity and creativity, contributing to the energetic feel of the music. The Original Dixieland Jazz Band is well-known for its innovative approach to jazz, and the use of stop-time exemplifies this characteristic, setting a vibrant, playful atmosphere in the song.