It's a new virtual surround sound format, which is supposed to duplicate the technology using regular 2 channel stereo headphones. Frankly, without suitable software that can simulate the depth and width of surround, it's going to be an underwhelming experience when it comes to music. With other types of audio, like ambient room noises, conversations, etc., it can make you feel like you are right in the middle of the action. I have a Now and Then Japanese Quad reel transfer to 8D audio and it sounds amazing with the right equipment, like you are right in the middle of the mix, and Karen is leaning on your shoulder singing right into your ear. The stuff on YouTube, however, is total BS.