I've had this equalizer for 2 weeks and it works very well. I recently got a Bose Wave radio that doesn't have a built-in equalizer and is much too bass-heavy for my tastes. So this allows me to tweak everything just right, and 15 frequency levels is more precision than I've ever had before. My music sounds much, much better now.

There is no distortion that I can detect even testing at volumes louder than I'll ever listen to.

The only thing I don't like is the blue LEDs lighting up when the eq's output is above a certain decibel level. They're very bright and I find them distracting. So I have to turn the equalizer's volume knob low enough to keep them off and compensate by cranking up my Bose to max/near-max volume.

It's worth mentioning that this is not a generic product. This is the Radio Shack model 32-2059.