The use of this pedal is very simple. One branch, it checks the input level through the VU meter (which is a little gadget, but gives a most sympathetic to this pedal) and the level is adjusted using the input gain knob. The second knob adjusts the level of the note an octave lower, then the overdrive section adjusts the level of saturated note an octave and the depth of saturation. Then you set the output level with the last pot. Operation is very simple.
I tested several models, because I wanted my guitar an octave that is warm and musical. I tried the behringer, Boss and Electro-Harmonix and I must admit that it is the one I was most impressed by its sound quality. He readily accepts to hold long notes, for against, it is impossible to play two notes at once with it, so pay attention to harmonics or notes lurking!
I discovered by accident in the octave pedal Behringer buying cheaply to try this I soon found indispensable. This pedal gives me what I want: a melodic bass sound and deep on my guitar. The price is high, but for someone like me who often uses this, I recommend it highly. The Electro-Harmonix is too rough for my taste and the Boss that works perfectly clear lack of character ...