McCoin has been involved with the Colorado Contemporary Music Association since it’s conception and has composed for and performed in many of their concerts. During the 80’s he acted and performed music for productions at the Denver Center for the Performing Arts, which led him to compose original scores and sound designs for numerous Theatrical and Dance productions across America and abroad.

During the mid-late 80’s, Mark began producing multimedia performances and sound installations, including the award winning "Music in Motion" and "Circadia". He also co-produced the award winning weekly public radio show "Terra Infirma". He was also one of the founders and musical director of Gamelan Tunas Mekar, a Balinese music orchestra.

Currently, McCoin owns "Brave New Audio" a recording and productions studio where he composes and produces music for CD, television (Animal Planet), animation, dance, films, installations, and for no reason at all.