In 2010, Steven Wan and his team of acoustic fans from China combined the portable player with the HIFI stereo and created the first Pocket HIFI whose SNR is up to 108 dB and can play the audio files of 24 bit/192 KHz SR perfectly in the world. The three world first of Pocket HIFI The first portable player can play the audio files of 24 bit/192 KHz. The first portable player whose jitter less than 5 picoseconds. The first portable player can promote a 300 ohm earphone. Regius walnut: black walnut in North America The outer casing material of the Pocket HIFI C4 player is made of the black walnut in North America. The black walnut had been called regius walnut. The pleasant vignette is formed by the clear, smooth glossy and wavelike grains and the clear annual ring. It provides each music fan a unique player.