Bests & Worsts Reviews from Amazon

It does dampen sound, but it's such an inefficient way to warm up or practice that it's not worth using. 1.) It's hard to breathe. It has two little nostril holes, so you'll be constantly pulling it off to take a breath. 2.) Your voice has nowhere to go and bounces right back down your throat. This is an uncomfortable experience that you don't want to endure for an entire warm up or practice session. 3.) It limits your facial movement so you will not create the same space that you usually would. I warmed up for 10 minutes with it. I regretted warming up to the top of my voice. The returning air pressure in the high range is very uncomfortable. I don't recommend singing at full volume because of the returning air pressure. I don't recommend this product for opera singers. After using it, my voice just felt weird and maybe a little hoarse the rest of the day.