A serious hand-built boost pedal. An elegant Class-A preamp stage that boosts your tone without changing its character. As with all Austone products, it is very quiet! The IN control sets how hard the stage is driven, (up to 10X with no distortion or 15X wide open with soft-shoulder clipping), while the OUT control sets the output level. Your solo comes along and your band won't back off? Stomp your Soul-O-Stomp on and you'll be heard! Proceed with caution, this thing can slap the front-end of you amp into distortion and pin your ears back! Formidable output as one guitar mag put it in a review. Each unit now comes standard with a red active LED indicator-while retaining true-bypass switching, and a Negative center 9V DC adapter jack (wall wart type). Has found world-wide use as a much needed booster and tone-warmer, while some like the slight touch sensitive overdrive they can achieve by opening-up the IN control and backing off the OUT or opening-up the OUT control to overdrive their amp. Used by electric cello players to equalize the volume of their pizzicato, (plucked), notes with their bowed notes, and acoustic- electric performers for soloing. Have a great feeling electric that lacks the power you desire in its pickups? Run it through a Soul-O-Stomp and fall back in love with that guitar! Use it last in long effects chains to restore signal loss. Perhaps the most useful pedal you can have in your arsenal! Find your own innovative uses for it, you'll never leave home without it!