Dr. Gary D. Cannon has developed a reputation as one of the most prominent choral conductors in the Seattle area. He currently serves as Artistic Director of a professional chamber choir, the Emerald Ensemble, and two community choirs: the Cascadian Chorale and the Vashon Island Chorale. He is known for engaging audiences through passionate performances, lively spoken remarks, and extensive program notes. Choirs often comment on his scholarship, gestural artistry and clarity, and humor during rehearsal. An enthusiastic devotee of new music, he has premiered over thirty works in the last ten years alone.

The Emerald Ensemble was founded in 2016 as a professional choir that engages the Seattle area's finest ensemble singers to perform repertoire from throughout choral history. The six Bach motets comprised their inaugural performance, with subsequent concerts featuring the Brahms Liebeslieder and music from England and Finland. Beyond traditional concerts, the Emerald Ensemble's mission is also to bring this music directly to people who are normally unlikely to benefit from it: for example, to those in schools, prisons, homeless shelters,  and hospice care facilities.

The Cascadian Chorale, a chamber choir based in the Eastside suburb of Bellevue, performs a breadth of mostly unaccompanied repertoire including newly composed music. Upon becoming their Artistic Director in 2008, Cannon has led them to new triumphs, including a fiftieth-anniversary recording, Welcome Home, which includes Randall Thompson’s Frostiana and works by William Billings and local composers. They have partnered with many leading Northwest composers, including Greg Bartholomew, Christopher Lee Fraley, the late Bern Herbolsheimer, Karen P. Thomas, Reginald Unterseher, and Giselle Wyers. They also present some of the most demanding music for small choir, including Renaissance madrigals and sacred works, motets of Bach and Brahms, English music of the last century, and contemporary premieres.

The Vashon Island Chorale, numbering 80–100 singers, is a focal point of its island’s arts community. During Cannon's tenure as Artistic Director since 2008, their membership and artistry have increased considerably and their repertoire has expanded to include such major works as Vaughan Williams’s Dona Nobis Pacem, Honegger's Christmas Cantata, and Bernstein’s Chichester Psalms. They have also premiered new large-scale works, such as Vashon Suite: No Bridges by Bronwyn Edwards and Abraham Kaplan's Eight Days of Chanukah and Song of Songs. They performed Orff’s Carmina Burana for the inaugural gala of the Vashon Center for the Arts.

At the invitation of Early Music Seattle in 2008, he founded and directed a volunteer, historically-informed Renaissance choir, Sine Nomine. Their repertoire stretched from the eleventh century (Pérotin’s Viderunt) to the eighteenth (Handel’s Dixit Dominus and the Bach Magnificat), with special emphasis on Josquin’s generation and Tudor England. For Sine Nomine's fifth anniversary, they presented such ambitious works as Tallis' forty-part Spem in alium. Cannon retired from Sine Nomine in 2015.

Even beyond those regular positions, he has made a deep mark in Seattle’s choral community. For over a decade he has served periodically as the Chorusmaster of the Northwest Mahler Festival. With them he has conducted reading sessions and prepared choruses for major works by Barber, Bruckner, Mahler, Prokofiev, and Vaughan Williams. He has on several occasions recruited and conducted choirs for a specific festival or concert, as for the Anna’s Bay Chamber Choir (2006, professional resident ensemble for Anna’s Bay Music Festival), the Earth Day Singers (2010, semi-professional chorus for composer David Hahn), and the Seattle Praetorius Singers (2015, for Early Music Seattle). He has guest conducted such prominent choirs as Choral Arts Northwest, Kirkland Choral Society, and several ensembles at the University of Washington. He is also active outside of the choral world, having conducted three times for Vashon Opera (including Madama Butterfly and The Tender Land).

As an undergraduate, Dr. Cannon studied at the University of California at Davis under D. Kern Holoman and Jeffrey Thomas, and sang in choirs directed by Paul Hillier. He then pursued graduate studies at the University of Washington in Seattle under Geoffrey Paul Boers and Abraham Kaplan, with a master class by Dale Warland. He completed his D.M.A. in Choral Conducting in 2014 with his dissertation From Oldham to Oxford: The Formative Years of Sir William Walton.