ADJ Products ELS15 BT,15" USB Blue Tooth Speaker Eleven Preset EQ on MP3 player (Normal, Rock, Pop, Classic, Jazz, Blues, Hall, Bass, Soft, Country or Opera), High power class A/B bi-amplified system designed to perform at maximum efficiency., Separate high frequency and low frequency Bluetooth Compatible Flyable & stand mountable, Treble, bass and volume output control, Microphone, and line level controls with master volume, Treble, and Bass EQ +/- 12 dB