Tom Anderson is a prolific professional vocal arranger who used to be an attorney. His career really took off when some guy from Oregon asked him to arrange a song for his college group. That guy was Peter Hollens and the group was On the Rocks. Tom stopped by my studio a few weeks back on his way to Memphis for NACC and we talked about how 4 Boyz from Philly started his acappella geekdom and a took a deep dive into vocal arranging where he talks about how instrumental orchestration has influenced his arranging style.
Tom Anderson - https://www.random-notes.com/
10 Ways to Improve your Acappella Recording - http://recordingacappella.com/podcast