These Alesis Micro Series are versatile, well designed very useful efx, with much needed reliable headroom ! ! ! And built to take the road. My fav use in studio is insert. When you need the extra gadget as your other efx are...."Preoccupied" This "Micro Enhancer" is, I believe an up dated version of the "Apex Aural Exciter" of the 70s.These gadgets can add a lot of sparkle to voices lead a/o harmony, guitar solos. They add harmonics, and you can tune both pitch and bandwidth. I've used one on a trumpet! Very well built reliable, consistent (really important in any app. And LOADS of headroom.. I've got two more (see pix).All three have Alesis OEM 9 VAC power supplies. All three work, and have been working fine since......Also- I've used these guys on whole live 5-6 pc LOUD rock band and again efx cut right thru. We've pix'd all three available Micros, and other available goodies. At this site you're bidding only on the described item.