I have used the on board pre's from our audio interface for the last 5 years. While they didn't sound bad, I had always wondered if getting a high quality external preamp would improve our sound quality significantly. I didn't want to spend this kind of money and get a 5-10% increase in quality; I wanted to be blown away. And my wish came true!!! Wow!!! First off, the signal to noise ratio is SO much better than what we were using previously... I record audio books for a living, so a quiet signal chain is crucial to our success; there are no guitars or drums to mask that hiss!!! This thing just made cleaning that noise out with noise reduction plug ins a thing of the past!!! Secondly, the actual sound quality of the preamp is pristine. I feel like I am finally hearing the true sound of my voice for the first time. Finally, the impedance selector is something I didn't know I needed until I had it. It allows me to change to tone of our mic to suit our other voice actors. Speaking of mic's, I use this with an SM7b, which is a notorious gain hog. I used to have to run a cloud lifter to get the gain up enough to make it usable. The cloud lifter is now acting as a door stop.