HPL2 Processor plug-in is released for free. A professional binaural conversion technology "HPL"(HeadPhone Listening) used by some Japanese label that produces high-quality high-resolution music when producing a sound source version for headphones. The conversion tool was released as a VST plug-in. (free) By using this HPL2 Processor plug-in, you will be able to listen to the same mix-balanced sound as you listen to a 2-ch stereo sound source with a speaker, even with headphones or earphones.