This equalizer, you spend less time tweaking controls and more time playing. Shape sound and eliminate feedback with 5 bands of equalization. With bass, middle 1, middle 2, treble, pres control knobs. Tone and volume control. Wide frequency range from 20 HZ to 20 kHZ. Auto and manual tuning mode. LED for effect on/off and battery check. Easy to read metronome on LCD display.Powered by 9V Alkaline