♫ Chorus students love this warm-up!......For middle and high school chorus. ♫ CHANGES KEYS AND ACCELERATES. ♪ I created this .mp3 file for the well-known number warm-up that has been passed on anonymously for years. This purchase is the .mp3 recording, which changes keys and accelerates with each new sequence. ♫ ASCENDING AND DESCENDING (4 times through){Vocals are only on the PREVIEW.}1, 121, 12321, 1234321, 123454321, 12345654321, 1234567654321, 1234567876543218, 878, 87678, 8765678,