The NY file extension is mainly related to a special Nyquist plug-in for Audacity. Nyquist was written by Roger B. Dannenberg and was intended to be used as a complete programming language for audio synthesis and analysis, with support for MIDI, audio recording and playback, file I/O, object-oriented programming, profiling, debugging and more. Audacity uses only a subset of Nyquist's functionality, allowing you to take simple Nyquist functions and use them to process audio data. Audacity doesn't include any support for debugging Nyquist code, so if you are trying to write a complicated plug-in, you may find it easier to get the full version of Nyquist and develop there, then turn it into an Audacity plug-in.