There are a number of songs I can do pretty much w/out look at the screen. I will glance up just to make sure I'm right on the lyrics and timing (e.g. when to start the verse or whatever).
Its very different (to me anyway) to sing along with an original vs. Karaoke (w/out the words).
I recently got drafted for a singing competition (not Karaoke). So, I've had to learn the song well enough to do it w/out the crutch of having a monitor. A few folks showed up to audition and were thrown off by not having the words.
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What's been odd is I really know the song, but I've caught myself singing the wrong verse at time... and then I'm saying WTF to myself. But I get up on stage, and it goes just fine.
On knowing the words bit-- it seems to me that its better (more important) to know the melody MORE than knowing the words with Karaoke. If the words are there, its one thing. But if you have no clue what the melody is, words aren't gonna help you one bit.
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