"Rachmaninoff's Vocalise, one of the most well-known of tunes for the voice, is here published in the original C sharp minor version (high voice), together with transpostions to B minor (medium) and G minor (low). A perface by Gordon Stewart (vocal coach at the Guildhall School of Music and Drama, London) provides historical context and a guide to performance. 

Which key do I need today? This has always been a conundrum for singers – even more so for singing teachers. A singer may sometimes want to perform a song in a different key; singing teachers often need to try different keys for their students. The Edition Peters 3-keys-in-one series provides an instant solution to this problem: the most widely-sung solo songs and operatic arias presented in three keys in one publication."