A multi-frequency booster with a 12 position frequency selector and a gain function. It allows you to choose which frequency you choose to boost. That is very important since it helps marry your guitar with whatever amp you are using.
If your guitar is too bassy, choose a high frequency to boost. If you have humbuckers and you wish a single-coil sound, choose a higher frequency. If you have a single coil and want to fatten it up, use a low frequency. The same goes with the amp.
This pedal can be used on a microphone for effects, bass guitar, keyboards, nylon electric, horns, digital mixes, the combinations are endless.