Alto Saxophone Solo - Level 1 - Digital Download SKU: A0.605587 By Katy Perry. By Esther Dean, Katy Perry, Mikkel Eriksen, Sandy Wilhelm, and Tor Erik Hermansen. Arranged by Kevin Busse. Pop. Individual part. 2 pages. Kevin Busse #4302577. Published by Kevin Busse (A0.605587). This is an exact transcription of Katy Perry's vocal parts for Firework in the easy key of C for Alto Sax