Sound Control - App-specific volume control
Equalizer APO - A system-wide equalizer for Windows 7 / 8 / 8.1 / 10 with channel remapping/copying capabilities
Volume2 - Volume2 is an advanced Windows audio mixer, a complete replacement for the standard Volume Control.
FxSound - Clearer Sound for Your PC. The new FxSound boosts your sound quality, volume, clarity and bass.
EarTrumpet - Volume Control for Windows
Boom 2 - Boom is a simple volume booster that lets you boost the volume of your Mac and your music files.