Justin Gruber began his musical endeavors on the tuba at the age of 9 and currently holds the Tuba position in the Winnipeg Symphony Orchestra. Justin's orchestral pursuit began in his junior year of high school when he won the Principal Tuba position in the Florida Youth Orchestra. He held this position for the rest of high school while traveling to Carnegie Hall in 2018 and the Midwest Clinic in 2019. An article in the Winnipeg Jewish Post detailed much of his life experience centered around this time. Before leaving high school, Justin was fortunate enough to attend the Boston University Tanglewood Institute, Curtis Summerfest, be a finalist in the New World Symphony Concerto Competition, a National YoungArts winner, and win the Kovner Fellowship from Juilliard.

Justin was awarded the President's Music Scholarship to attend the University of Miami's Frost School of Music. There, he studied with Dr. Aaron Tindall to pursue a bachelor's degree in music in professional studies, graduating in the class of 2024. He had the distinct pleasure of performing with Gerard Schwarz and the Frost Symphony Orchestra on many occasions. He is also a valued National Society of Leadership and Success member. During his first year as a cane, he won 3rd prize in the Leonard Falcone International Tuba Artist Solo Competition and became an Associate Member of the Chicago Civic Orchestra. Shortly after a summer in Greensboro, NC, as an Eastern Music Festival Orchestral Fellow, Justin won the Principal Tuba position with the New Mexico Philharmonic performing their 2021-22 season.

After his debut season in NM, Justin attended the Brevard Music Festival as an Orchestral Fellow. He is a Jan and Beattie Wood Concerto Competition finalist. Shortly after his time at Brevard, he was Principal Tuba with the Chautauqua Symphony Orchestra for the remainder of their 2022 season. Before winning his current position, he also had the pleasure of performing with the Sarasota Orchestra and Ballet. In the same period, Justin became a Yamaha Young Performing Artist and was awarded a fellowship to attend the Aspen Music Festival studying with Warren Deck. Justin has also been hand-selected to be a Denis Wick Performing Artist starting in 2024. Justin is a proud member of the Music Professionals of Manitoba. Through his private studio, he continues to educate the next generation. He has given lessons and masterclasses at Sistema Winnipeg, Camp Arnes, the Manitoba Band Association, and the University of Manitoba’s Desautels Faculty of Music. Justin began composing at 11, and his continued passion for making music fueled his rise in composition. He has such a passion for the music of Dmitri Shostakovich, Pyotr Ilyich Tchaikovsky, Béla Bartók, Gustav Mahler, and Richard Strauss.

In March of 2023, Justin won Special Prize in the 2nd ISAC International Popular Music Composition Competition for his piece, "Bumbling Naivety". In June of the same year, he performed in the premiere of his piece, "Fanfare for the Winners," which was programmed for the YYPA 2023 weekend celebration. In October of the same year, The Pacific Chamber Orchestra selected Justin for their Dream American 2023 workshop and performance of a rendition of "This Road Alone," “Grand Beach,” was handpicked in a call for scores by the Untitled Ensemble for the 2024 Land of Lakes Showcase. In addition, “Clandestinity” was one of the winners recorded in a call for scores by the Fivemind Reed Quintet. Arrangements entitled: “Ballet Medley” and John Powell’s “How to Train Your Dragon” were specially commissioned for the STAMPS Brass Quintet of the University of Miami for collaborative performances in their Spring 2024 Senior Recital. Justin's piece "Beneath the Crypt," written in 2022, premiered with the Frost Symphonic Winds in the same month, just before he could return home to graduate. After Justin’s second season in Winnipeg with his degree from Miami, he attended the València International Performing Arts Summer Festival in Spain. The world premiere of “Goodnight Lenny” was performed by the València International Contemporary Ensemble.