Kasaei’s virtuosity on the ney quickly became evident, and he went on to become one of the most influential ney players in Persian music. His unique sound, distinguished by its purity and emotional depth, was a significant breakthrough for the instrument. Historically, the ney had struggled to achieve a consistent and pure tone across its range, but Kasaei’s innovative approach to breath control and the articulation of notes allowed him to produce a remarkably clear and resonant sound. This development helped the ney gain wider recognition as a prominent instrument in Persian classical music, elevating it to the level of other traditional instruments like the tar, setar, and santur.

Kasaei’s ability to produce nuanced tones in both the lower and higher registers set him apart, allowing him to showcase the ney’s full emotional range. His efforts also included introducing the ney to orchestral performances, starting with his groundbreaking work in 1950 with the Radio Army Orchestra in Isfahan. By the late 1950s, Kasaei was performing on Golha (a popular Iranian radio show) and collaborating with a host of renowned musicians, such as Mohammad Reza Shajarian, Jalil Shahnaz, and Ali Tajvidi.