Rock Band
50 Achievements
1,000
80-100h
Xbox 360
Crooner
Finished Vocal Solo Tour on Hard
40
How to unlock the Crooner achievement in Rock Band - Definitive Guide
The game becomes a lot more critical of your pitch and timing on hard. It will really help if you can learn the melody of the song (listen to in practice mode). If you hum instead of singing the lyrics it can also help as this is one less thing to worry about.