Trinitas Symphony Orchestra (TSO) was first founded on Tuesday, August 16, 2011, by Mr. Hendry Limandry, who has been teaching at SMA Trinitas since 2010. Initially, Mr. Hendry was assigned to lead the school choir, which had previously existed but was repeatedly disbanded due to a lack of interest and discomfort among students. After a year of facing similar challenges, he realized that to attract students, the choir needed something more engaging—better songs and music. This idea eventually led to the decision to form an orchestra. At that time, Mr. Hendry only knew one student who played the violin, Cornelia Amy. To find more musicians, he collaborated with the school principal, Mr. Suro Mulyono, who was conducting a student talent survey. Through this effort, Mr. Hendry discovered many students skilled in playing musical instruments like violin, piano, flute, saxophone, and more. These students became the first generation of TSO, including talented individuals like Cornelia Amy, Stefan Singgih (saxophone), Evie Christiana (flute), Levina Mahardhika C, Maria Desiana Claudia, Fiona Meryl, Kenan Mahesa S (piano), Moses (bassist), Michelle Guido (drums), Mediatrix, Deslyn and Sharleen (synth), Adit, Aguina S, Birgitta (vocals), and Christopher Susanto, known for his dedication. TSO’s first rehearsal took place in the school library after school on Tuesday, August 16, 2011, where they played the beautifully arranged spiritual song "Kau yang Terindah" by Robert and Lea.