My OC, Whisper Call, off on her own demonstrating another aspect of her voice magic.
 
She is a fairly good singer under normal circumstances, but she can use her magic to enhance her singing voice to levels that match most professional singers. She enjoys singing as a hobby and often goes off to practice it.
 
There are two reasons why Whisper doesn’t exploit this magic for personal benefit (other than just for fun). The first is that she considers it cheating and would never use it to win a talent contest or try to become a professional herself. The second, even bigger reason is that while she loves to sing, she is deeply self-conscious of her singing and will never do it where other ponies can see or hear her. If somepony came upon her while she was singing, Whisper would faint from embarrassment.
 
It is possible for Whisper Call to project her voice and enhance her singing at the same time, although it would be more difficult and draining for her.