A free app for Android, by Hot Storm Apps.
Super Volume Booster: Sound B is a free audio volume booster app for Android. This tool is capable of boosting the sound volume of any audio file. With it, you will be able to play your music at a much louder volume. You can even choose to have your music play in a new format, such as a bass-boosted wav file. The app is very simple to use. All you need to do is to select the audio file you want to boost, and then press the boost button.
It has many audio effects, including volume boost, bass boost, 3D virtualizer, and more. The sound spectrum is also presented when you are playing music. It allows you to have a better music experience. You can use this tool for all kinds of music, such as MP3, WAV, OGG, FLAC, and more.
It has an equalizer and a virtualizer. The former allows you to choose the sound frequency to boost. The latter lets you use different sound effects to the music. It is also possible to set the volume of the virtualizer as a fixed value.