This gentleman is flat. Can you tell? Now that I've removed my fingernails from the ceiling, let's talk about flatness. We all do it sometimes. Singing under the correct pitch can be caused by singing notes that are out of one's natural range, insufficient breath support, or mismatched vowels. Try this: Sing or speak a bright "ee" sound, very nasally, in the front of your mouth. Now, sing or speak the same "ee" in the back of your throat. The pitch goes down, doesn't it? Try it in reverse: Think of singing "Somewhere, over the rainbow." Sing the "some" in the very back of your throat, then try to vault up to "where." It's eight notes away, but unless you really know where you're heading, you probably feel very insecure finding that high note. People who sing flat fail to quickly adjust to changes in vowels and changes in pitches, or they fail to maintain adequate air flow while they sing. They don't hear it or feel it, so they don't fix it.

Can you fix flatness? Yes! First, hear it: Record yourself singing and then listen to the results. Most people dislike hearing the sound of their own voice, but try to be detached about it, and just listen for pitch accuracy (or ask a friend to listen, and be honest with you). Do you have trouble matching pitch on the highest notes, on the descending lines, or ascending lines? Then, think about what's going on when you're flat. Which words or syllables tend to make you sound flat? What's happening in your mouth and throat when flatness occurs? Do you feel sensations in your throat such as squeezing, stretching, tightening, grimacing? What are your abdominal muscles doing (or not doing) when flatness happens?

Now that you are aware of your particular recipe for flatness, bring in the technology. I love my Sabine MetroTune 9000 tuner (about $29.95 on Amazon.com) for its awesome, Harry Potter-esque name and model number but also for its ability to show singers exactly which pitch they are singing. Even though I have perfect pitch, I'm not infallible -- I need help hearing sharp and flat pitches, too. When the tuner tells me I'm singing a flat note or series of notes, I adjust my mouth shape and reinforce my breath support, and sometimes I'll draw an "up" arrow over the pitch in my music to remember to make those modifications every time I sing. Like many people I have a tendency to go flat on descending lines (think of the beginning of "Joy To The World"), so I slightly adjust each pitch as I head down -- I might open my mouth or slightly brighten the vowel. It's amazing how just a slight change can make all the difference.

There is computer software to test and train the flatness out of your voice as well: The Pitch Perfector can do this in the privacy of your own home, for only $67. If you like sitting in front of a desktop computer, this is probably a good option.

For flat-fighting on the go, use a smartphone app. I just purchased ClearTune for $3.95 and don't know how I managed without it. It's a little slower than the Sabine, but it gets the job done. Last week I used it to reinforce intervals with a children's theory class. Several kids were absolutely certain they were singing a fourth interval (think "Here Comes The Bride") when in fact they were singing sharp thirds and very flat fourths. I held up the tuner, and they realized how far off they were. Immediately they increased their breath support and sang a brighter tone to achieve the correct pitch. The tuner will save us hours of practice time, because we'll know instantly if we're singing on pitch.

When you're a world famous singer, you can use Auto-Tune to cover all your pitchy sins. But it's cheaper and better to fight flatness with healthy vocal technique -- just tell 'em you're using "Ought-To-Tune."

I wasn't aware of Jay-Z's hilarious "D.O.A. (Death Of Auto-Tune)" until recently, but I think he's right -- it's overused. (Maybe by his wife, too?) So, get a tuner and practice basic vocal technique, and you'll never sing flat again. Unless you want to end up on YouTube. . . . I like it when she takes out her gum . . . .