Famous peripheral manufacturer Razer has released an audio software that can simulate 7.1 surround sound effects - Razer Surround. Moreover, Razer Surround is currently in a limited-time free usage phase and can be freely downloaded, installed, and used before December 2013.
Razer Surround uses an exclusively developed revolutionary audio engine which aims to deliver 7.1 virtual surround sound through stereo headphones for users. Razer Surround is compatible with all stereo headphones. Users can create 3D surround sound or a virtual 7.1 soundscape as per their needs. If you are using Razer's headphone products, you can also experience the audio effects individually calibrated by Razer for its own products.