He is a Bulgarian jazz musician and kaval player. Theodosii Spassov started playing the kaval at the Kotel Music School and the Dance and Music Academy in Plovdiv, Bulgaria. The kaval, a wooden eight-hole flute primarily associated with shepherds, is one of the oldest instruments in Europe, rich in tones and technical possibilities. Theodosii Spassov has developed a unique style by encapsulating traditional folklore, jazz, fusion and classical music.

For over 20 years, Theodosii has toured Europe, Asia, Middle East, Australia, Canada and the United States and has won numerous awards and recognitions.

In Bulgaria, Theodosii Spassov is a national celebrity and musical hero, and he was recently awarded the “Best Musical Artist of the Year” prize. He is the director of the world renowned “PHILIP KOUTEV National Folk Ensemble”. Theodosii is a member of the Irish music and dance company "Riverdance". He is currently a soloist at the Bulgarian National Radio.