Learn how to say Polyphonist correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word polyphony:
noun (plural polyphonies)
[mass noun] Music
the style of simultaneously combining a number of parts, each forming an individual melody and harmonizing with each other:
his love affair with 16th-century English polyphony
[count noun] a composition written, played, or sung in polyphony.
the ability of an electronic keyboard or synthesizer to play a number of notes simultaneously:
the polyphony is a standard 32-voice