Complex sentence: Richter's performances were known for their soulsearching, intense and festive character, but he avoided the fluctuations in tempi that were then characteristic of the prevailing Romantic manner of conducting Bach.
Split into simpler sentences: Richter's performances were known for their soulsearching, intense and festive character. He avoided the fluctuations in tempi that were then characteristic of the prevailing Romantic manner of conducting Bach.