The ASUS Xonar U3 is a portable, pocket-sized audio solution that delivers an upgraded audio experience for notebook users. Slightly larger than a standard USB flash drive, the U3 is designed for users looking to turn their notebooks into a personal high fidelity audio center complete with Dolby and GX2.5 support. The onboard audio solution for most notebooks in the market offers just the bare minimum in sound quality and controls. The Xonar U3 with built-in headphone amplifier is the best solution for those users who use their notebooks as personal entertainment centers. Weighing only 25g and easily fitting in a pocket, the U3 enhances treble and bass while driving high fidelity headphones with impedance up to 150 ohms. Also built-in is Xonar exclusive hyper-grounding technology, which works like a watershed to separate audio signals from noise to provide clean and clear sound. Installation is easy and with multiple pre-set equalizer settings and modes for gaming, music, movies and headphone use, upgrading notebook sound is quick and simple. Realistic audio with Dolby and GX 2.5 support The Xonar U3 offers a wide range of Dolby Home Theater Technology including: Dolby Headphone, Dolby Pro Logic IIx, Dolby Digital Virtual Speaker and Dolby Digital Live. Each plays its part in delivering cinema-quality sound so users can experience movies and music in high-quality and discrete multi-channel surround sound. The Xonar U3 is also ideal for gamers, with built-in GX 2.5 Gaming Audio Engine which is compatible with EAX 5.0 audio signals. This enables up to 128 different sound effects to be played simultaneously for a realistic 3D experience.