This device has loads of uses. One of my favorites is to place it in the foot-switchable effects loop of a guitar amp for an clean, instant 10-or-so dB boost for solos, etc. I also use one in my stereo system - I have an old preamp which can't handle the audio output from my DVD player w/o clipping. LL Shifter between the two and problem solved. I've also used it as a pseudo direct box to convert to low Z and feed the line outputs of a guitar preamp down the snake to the PA. If you have ground loop hum in your system, try strategically employing one of these babies and you can probably avoid chopping the ground plug from your AC cords. A great value that has many uses.