Marshall Noah Altman is a Nashville-based A&R for Nettwerk Music Group, and a record producer and songwriter who owns the Galt Line studio in Nashville, Tennessee.

After graduating high school in Huntington Beach, California, Altman attended college at UC Santa Barbara, for a major in business and a minor in music.

He eventually left Columbia to pursue being a full-time record producer in 2005,[6] starting the Galt Line Music label and a studio in Burbank, California.

[9] At the Galt Line he would go on to produce for a variety of artists, achieving commercial success with albums such as Kate Voegele's Don't Look Away and Matt Nathanson's Some Mad Hope.

His other producer credits include albums for: Natasha Bedingfield, Gabe Dixon, Walker Hayes, Rosi Golan, Adema, Matt Wertz, Trevor Hall, Caitlin Crosby, Kimberly Caldwell, and Tom Morello and others.