A free program for Android, by Leanderoid Development – Audio Productivity.
SpotEQ31 – 31 Band Equalizer For Left and Right Side is a free audio equalizer app for Android. It is built to provide you with a customized listening experience, whether you’re a casual music player or a power player.
With this app, you can adjust the frequency range of the left and right audio channels separately, allowing you to customize your music experience. You can adjust each channel with a separate slider, and even set the minimum and maximum volume of each channel.
There are several different music presets available in the app, from bass to classical, jazz, pop, rock, hip hop, and more. You can also create your own custom music presets. You can save the settings you make and load them back whenever you want.
You can also set the equalizer to be on or off. If you have problems with the audio connection, you can try to pause or play the music.