Like a mega super deluxe octaver and it fulfills exactly what we need in the band. It gives a lower octave and also polyphonic. It has other buttons with which you can tune the sound in a quite useful way. It is basically a Mu-Tron so fat fat bass... My teammates praise it, the audience says wow how strong... so what can I say, if you want fat bass and a sound that makes you taller by 3 meters or more, go ahead and buy it!