I've only had a little time to practice with the Better Voice Vocal Training tool, and just after a few times on the 1st adjustment, I'm hearing more clarity in my James Earl Jones type of lowest notes, which were severely damaged by a throat infection years ago. Have desperately tried to recover this ability for years, unable to afford a speech therapist or specialized vocal coach. So I invested in this little tool instead, and already I'm seeing what it can do. I can already hear that by the time I work up to the 5th level, that the changes in my abilities will be night and day. My high notes weren't as badly damaged years ago, but it still became extremely hard to hold a proper tremolo, slide, flat-texture extended note, ect ect, with breaks, a shift in correct tremolo pitches, and scratchy vibrations taking over my higher registers. Already, these have improved too. This device is one that, even on the first setting and just one practice, you can already hear changes. My advice is that if you have a particular way of singing a certain note or way, emphasize trying your best to make sure your throat, chest airflow direction, and usual methods reflect in the way you hum and push air into it. I started out just with simple scale excersizes, and found better results when I payed a lot more attention to replicating my techniques as much as possible into it. It made a huge difference in my lowest, organ-pipe from-the-stomach-going-up type of note, using that "stomach valve open" (singers will get it lol) airflow rather than just a normal note hum. Right away, that lowest register became so much more clear. I heard the remnants of my low voice for the first time in forever. I can't be happier and this tool was worth every penny. Wether it's standard scale hums or honing a certain specific method, you will hear improvement from the get-go. This is Trìet Villé, author of The Reaper Of Mayhem - signing out!