ViPER4Windows is a free audio processing software created by ViPER520, a member of the Vipre audio team. It is an audio enhancement software that can be used to improve the sound quality of audio files and audio streams, such as music and movies. It includes many features such as 10-band equalizer, ViPER Bass, ViPER Clarity, ViPER Reverb, ViPER XBass, and more. The software also includes a system wide equalizer, which can be used to control the overall sound output. ViPER4Windows is very lightweight and requires minimal system resources. It is compatible with Windows 7, 8, and 10.
Razer surround does not provide any of the same features unless paid for, you have included it as free, nor does it provide IRS or proper volume boost.
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It does not provide any 3D effects, but allows much more control. You can use different parametric filters and graphic equalizers, apply effects on selected audio channels and devices (even microphones!) AND use convolution with impulse response. You can also use as many of each effect as you can, with different settings and on different channels.