Polyphone is a "soundfont editor" that allows for creating and editing digital musical instruments for use with midi keyboards and synthesizers. It can read and write the sf2, sf3, and sfz soundfont file formats and can import sfArk format files. Alternatively, WAV file samples can be imported to build musical tones directly from sound files. A number of sound processing tools are included to perform pitch detection, loop creation, sample equalization, and more. Plus, a built-in virtual keyboard allows users to test their new soundfonts prior to loading them on a midi device. The Documentation section of the Polyphone website includes reference materials, user tutorials, and technical documentation for developers. Polyphone can be downloaded for Windows, macOS, and several flavors of Linux.