Wagner began writing the opera Parsifal in 1857 but didn't complete it until 1882. It's first performance was given at Bayreuth just 4 months before his death. It is loosely based on a 13th-century epic poem of King Arthur and his quest for the Holy Grail.
Randall Malmstrom's beautiful arrangement of the music for 8-part Trombone Ensemble is noble and spiritual.
This 4-minute excerpt contains much of the Introduction or Vorspiel and is appropriate for advanced performers.
The instrumentation is for: 2 alto trombones, 4 tenor trombones, 2 bass trombones