The pianoforte trios of Haydn are perhaps the only-works of first-rate artistic importance in which there is no doubt that the earlier stages of the new art do not admit of sufficient polyphony to give the instruments fair play.
In the choral numbers of the five masses, and in the oratorios Die Heilige Elisabeth and Christus, the rarity of fugal polyphony acts as a drawback.
Bach himself is known to have executed it in a very polyphonic style, and this for the excellent reason that plain chords would have contrasted so strongly with the real instrumental parts that they could not fail to attract attention even in the softest tones of the harpsichord or the organ, while light polyphony in these tones would elude the ear and at the same time perfectly bridge over the gap in the harmony.
In the new art the concentration of attention upon form, as a more important source of dramatic interest and climax than texture, resulted in a neglect of polyphony which seriously damaged even Gluck's work, and which always had the grave inconvenience that while the new methods of blending and contrasting instruments stimulated an increase in the variety, if not in the size of orchestras, there was at the same time extreme difficulty in finding occupation for the members of the lower middle class of the orchestra in ordinary passages.
Where the orchestra shows that Parsifal is becoming half-conscious of his quest while Kundry is beguiling him with memories of his mother, - and also during the two changes of scene to the Hall of the Grail, where the orchestra mingles the agony of Amfortas and the sorrow of the knights with the tolling of the great bells, - the polyphony is almost as dramatic as in Tristan; while the prelude and the Charfreitagszauber are among the clearest examples of the sublime since Beethoven.