He has also played at numerous chamber festivals including the Sitka, Park City, Manchester (VT) Music Festival and Casals Festivals.
Sundance Film Festival | Cannes Film Festival | Toronto International Film Festival | Glastonbury Festival | Edinburgh Festival | Royal Festival Hall | Venice Film Festival | festival | Tribeca Film Festival | Salzburg Festival | Montreux Jazz Festival | Edinburgh Festival Fringe | Pablo Casals | Oregon Shakespeare Festival | Monterey Jazz Festival | film festival | Bayreuth Festival | Metro Manila Film Festival | Newport Jazz Festival | Locarno International Film Festival | International Film Festival of India | Festival of Britain | Glyndebourne Festival Opera | Coachella Valley Music and Arts Festival | Viña del Mar International Song Festival | Vancouver International Film Festival | Sanremo Music Festival | Aspen Music Festival and School | Tanglewood Music Festival | Fuji Rock Festival |
Ohyama has always been in demand as a violist and has performed throughout the United States and abroad as recitalist and chamber musician at festivals including Casals Festival, Kuhumo International Festival (Finland), Johannesen International Music Festival (Canada), Okinawa Moon Beach Music Festival (Japan), Brescia and Bergamo Festivals (Italy), Chamber Music Northwest, Sarasota Music Festival and Caramor Chamber Music Festival.
In 1955, she was invited by Pablo Casals to perform chamber music with him at the Casals Festival in Prades, where she returned for at least seven subsequent festivals.
March 3, 2007, Casals Festival, San Juan, Puerto Rico: Puerto Rico Symphony Orchestra, San Juan Philharmonic Chorale; Andreas Delfs, conductor; Heidi Grant Murphy, soprano; Nathaniel Webster, baritone.
She has performed at major festivals such as Marlboro, Ravinia, Banff, Bargemusic, Manchester, Aspen, the Ottawa International Chamber Music Festival, Lenaudiere, and the Pablo Casals Festival as well as at various pop and jazz festivals like Lollapalooza and the Festival Internacional Jazz Barcelona, to name a few.