Complex sentence: Taffanel spent 30 years building a substantial career as both soloist and orchestral player, becoming known as the foremost flutist of his time and reestablished the instrument in the mainstream of music.
Split into simpler sentences: Taffanel spent 30 years building a substantial career as both soloist and orchestral player, becoming known as the foremost flutist of his time. By doing so he reestablished the instrument in the mainstream of music.