Rob Mathis - President

Rob has been singing with Calliope (bass) since 2015. He has many years of experience in numerous choral groups.  When not singing, or sometimes while singing, he enjoys riding his bike, doing science, and going on real and imaginary adventures with his friends.  Rob has a PhD in Biology from MIT.

Sabrina Ellis - Board Member

Sabrina Ellis has been a Calliope member (alto) since 2015. She served as president of Calliope from 2020-2023. Previously she served as the clerk on Calliope’s board. Sabrina attended New England Conservatory and Harvard University and has years of experience singing as both a soloist and a chorister. She was a member of Chorus Pro Musica and the Coro Dante in Cambridge and performed with choruses in New York and in Italy.

Sabrina has administrative and managerial skills and worked at the Harvard Medical School. She is the music director of an exciting company in Verona, Italy called Opera Talk Italy.

Colleen Martin — Board Member

Colleen Martin has been a Calliope member (alto) since 2013. She served as president of Calliope from 2015-2020 and was the section leader for the altos for two years and the recipient of the Kathy Koniuto Chair in 2015. As a marketing professional with experience in marketing planning, research, communications, project management, and strategic planning, she has worked in both for-and non-profit organizations. In 2019, Colleen was recognized by the Massachusetts State Legislature for her Civic Engagement and Community Service. Currently she runs her own company, CRM Marketing services.

Karen Brim - Board Member, Clerk

Karen Brim is a dedicated double bass player who keeps very busy in community ensembles around the Boston Area.  Aside from Calliope, she plays regularly in the Wellesley Symphony and Narragansett Bay Symphony Community Orchestra.  Karen has a master's degree in Bio Engineering and works as a Project Manager in the software industry.

Yanko Sheiretov— Treasurer

Yanko Sheiretov joined Calliope as a clarinet player in 2008 and the board in 2017. He's very active in the Greater Boston avocational music community and has played with many symphony orchestras and opera houses. He currently holds the principal clarinet positions at the Wellesley Symphony Orchestra and at Calliope. Yanko holds a Ph.D. in electrical engineering from MIT and is currently employed in the medical device industry.

Stephanie Beatrice — Music Director & Conductor

Stephanie Beatrice joined Calliope as our new music director and conductor in April 2023.  Stephanie currently serves as Music Director of the Boston based Opera Company - Cambridge Chamber Ensemble. As a conductor she has been accepted into programs such as Distinguished Concerts International New York as a Conducting Mentor, working with DCINY musicians at Carnegie Hall, and with composer Sir Karl Jenkins in performances of his works Symphonic Adiemus, and the Armed Man.  

Beatrice’s tutelage extends to notable conductors Mark Shapiro (The Juilliard School) Michael Adelson (New York Philharmonic), Erica Washburn (New England Conservatory), Simon Carrington (King Singers), Antonello Allemandi, and Doreen Rao. Beatrice holds degrees from the New England Conservatory of Music where she earned her MM in Choral Conducting, and the University of Maine earning a BME in Music Education, and is currently studying Orchestral Conducting at The Juilliard School - Extension Division.


Julia O’Toole — Founder, Artistic Director Emerita

As founder and Music Director of Calliope, Julia delighted in the opportunity to lead musicians from a variety of Boston area choruses and orchestras. Having worked with several of these organizations previously in the capacity of vocal and performance coach, familiarity with the passion of their members inspired the dawn of Calliope. She earned a BFA in vocal performance from Boston University, a Master's Degree in Musicology from Brandeis University, and a PhD in Historical Musicology from Boston University. She taught voice throughout the Boston area, substituted as conductor for local organizations, and regularly teaches, publishes, and presents on various musicology topics.


Patrick Valentino — Former Music Director & Conductor (2019-2020)

John Verkuilen — Interim Music Director (2018)

Jacques Dupuis — Former Music Director & Conductor (2016-2017)