Stallcop moved to Phoenix in 1973 to take his current  position as double bassist with The Phoenix Symphony. He was also appointed principal double bass in the Flagstaff Festival of the Arts summer orchestra in 1993, after serving as assistant principal since 1983. 

 As a professional double bassist with a major symphony orchestra, a significant amount of his creative effort has been spent on works which feature the double bass.  He has written works for double bass and orchestra, for solo bass, bass with accompaniment, two sets of bass duets, and several chamber music works.  He won the 2004 International Society of Bassists Composition Competition for solo double bass with his work entitled Vision Quest, for double bass and piano.  It was premiered in 2005 at the ISB conference in Michigan.    

The Phoenix Symphony Orchestra has performed nine of his orchestral compositions, including Millennial Opening in 2002, Calypso Round in 2002, and Sunscape, commissioned in 1987 by the Arizona Diamond Jubilee Commission.  His music is performed by symphonies, festivals, chamber musicians, and youth orchestras around the country. 

Stallcop became seriously interested in chamber music in 1980. He presented annual concerts of his new compositions at the Kerr Cultural Center in Scottsdale, Ariz., from 1980-84. In 1983, he founded the Arizona Composers Forum and served as its president and executive director from 1983-89. During this period, ACF presented 46 concerts in Phoenix, Tucson and Flagstaff, a series of 12 lectures, and a weekly radio program featuring music of Arizona composers. He presented concerts of his own chamber music on this series annually from 1985-89. 

At the keyboard, Stallcop has been active in classical music, jazz, free improvisation and the performance of his own music. After playing classical piano and rock-and-roll in his teens, he turned to improvisation in the 1970s. Since 1977, he has performed almost exclusively in free improvisation, both as a soloist and in ensemble. In 1998 Arizona University Recordings released his CD of solo piano improvisation, Dreamcatcher (AUR/Horizon CD 3007). It received Grammy nominations in two categories. 

In 1995 Stallcop was awarded the Performing Arts Fellowship in Composition by the Arizona Commission on the Arts and was appointed to serve on the Phoenix Arts Commission from 1986-89. He is published by BassScores and the American Composers Alliance (ACA). He has been a member of Broadcast Music, Inc. (BMI) since 1977, and was elected to ACA in New York in 1982. He has been a member of the American Federation of Musicians since 1966.

He has been active as a private instructor of composition, music theory/ear training, double bass, and piano since 1974. In 1995 he taught double bass for the Arizona School for the Arts and has been an adjunct professor of music theory in the Maricopa Community Colleges. In 1996-98, he was the music program director and instructor of creative music at Horizon Charter School in Chandler and Phoenix.   

His major teachers include Robert Suderberg, William Bergsma, and Chinary Ung for composition, Ring Warner and Steve Brewster for double bass, and Frits Scavenius for piano. Mr. Stallcop received a Bachelor of Music degree from the University of Washington and a Master of Music degree from Arizona State University, where he was awarded Outstanding Graduate in Music History, Theory, and Composition.