Simple and with the most necessary permissions

The EQ has five bands. Unfortunately, no real deep bass controller, because the lowest frequency is just 60Hz, as the highest with 14kHz.
By contrast, the Bass Boost brings good results: Clean, dry, powerful bass. No distortion or blur.

Conclusion: Due to the fast access on the status bar, the app is profitable. However, the EQ does not provide extensive settings. Although the virtualizer brings another extra on board, but that less pleasing sounds.