DFX Audio Enhancer - Formerly known as DFX Audio Enhancer, FxSound Enhancer instantly boosts the sound quality of the music on your PC.
PulseEffects - Limiter, compressor, reverberation, stereo equalizer and auto volume effects for Pulseaudio...
Equalizer Pie - Equalizer Pie is a free audio manipulation application for OS X.
Equalizer APO - A system-wide equalizer for Windows 7 / 8 / 8.1 / 10 with channel remapping/copying capabilities
FxSound - Clearer Sound for Your PC. The new FxSound boosts your sound quality, volume, clarity and bass.
SteelSeries Sonar - SteelSeries Sonar is a free audio program for PC that lets you make real-time adjustments to sound being played or sound being recorded.