Sasha Johnson began his musical training at age 16, studying brass chamber music and tuba with Sam Pilafian at the Empire Brass Seminar of the Boston University Tanglewood Institute. He went on to study at the University of Toronto with both Mark Tetreault and Murray Crewe of the Toronto Symphony, with Toby Hanks at the Manhattan School of Music, and with Alain Cazes at the Conservatoire de Musique de Montreal. His additional private teachers have included Arnold Jacobs, , Mel Culbertson, Richard Erb and Alan Baer.

In 1997 Sasha became the first Canadian tuba player to be accepted into the Orchestra Academy of the Berlin Philharmonic. This program trains a small number of young professionals in the sound, style, traditions and standard of the Berlin Philharmonic Orchestra. Having begun his professional career in Berlin, Sasha went on to perform with many other European orchestras including the Berlin Symphony, the Berlin State Opera, the Radio Orchestra Berlin, the Orchestre Symphonique de Radio France, The Orchestre de Paris, the Ensemble Modern and the Orchestre Nationale de Bordeaux. He has performed in such music festivals and concert venues as the Lucerne Festival, the Festivale d'Aix en Provence, the Concertgebouw, the Konzerthaus Wien, the Theatre Champs-Elysée, the Schleswig-Holstein Festival, the Salzburg Festival the BBC Proms, Tanglewood, Ravinia, and Lincoln Center, under such eminent conductors as Claudio Abbado, James Levine, Pierre Boulez, Essa-Pekka Salonen, Paavo Jarvi, Charles Dutoit, Kurt Masur and Seiji Ozawa.

Sasha returned to Canada in 2001 and has established himself as a prominent performer and pedagogue. He has performed as a regular extra with the Orchestre Symphonique de Montreal, including tours to Europe and Japan; the National Arts Centre Orchestra, and the Toronto Symphony, including playing their 2009/2010 season. He is the instructor of tuba at the Glenn Gould School of Music and instructor of tuba and chamber music at McGill University, as well as an instructor of low brass and chamber music at the National Youth Orchestra of Canada. In January 2009, Sasha was appointed principal tuba of the National Ballet of Canada Orchestra. Sasha is a founding member and administrative director of the Canadian National Brass Project.