Vocal Coach: Micah Graber explains to us why Vocal training is an essential part of the Musical Theatre experience. 
A vocal coach, also known as a voice coach (though this term often applies to those working with speech and communication rather than singing), is a music teacher, usually a piano accompanist, who helps singers prepare for a performance, often also helping them to improve their singing technique and take care of and develop their voice, but is not the same as a singing teacher (also called a "voice teacher"). Vocal coaches may give private music lessons or group workshops or masterclasses to singers. They may also coach singers who are rehearsing on stage, or  who are singing during a recording session. Vocal coaches are used in  both Classical music and in popular music styles such as rock and gospel.  While some vocal coaches provide a range of instruction on singing  techniques, others specialize in areas such as breathing techniques or  diction and pronunciation.