Using BlackPlayer EX from few days, it is a good music player with Minimal User Interface. but have good customization options like Themes, Background Color Accent, Transition Effects and Translucent Windows to name few. very simple Library with Tabbed Tracks, Folders, Artist, Albums, Genres. it is easy to use and works flawlessly. I really like some audio features like Gapless, Crossfade but the most important feature is Equalizer which is inbuilt in application but you can also use any stock EQ(Audio Fx) too. it is easy to switch.
Audio Quality is Super good, Deep Bass, Treble and good Mids.i am using Viper4Android(EQ)with it it is a good sound experience and last it is available on play store for 35Rs.