DADMONSON
Concentrate on "feel" more than listening. When the song feels right...it is. If you have to rely on the monitors to hear yourself then you are handicapping yourself. Monitors are only there for pitch while you "Perform" the song. Turn your voice down in your headphones, pull one ear OFF when practicing to get used to feeling the sensations in your throat, head and ears. This builds your confidence and comfort such that you KNOW when its right. If you are trying to do songs "emulating" a famous singer exactly and require that much monitoring then there is a problem (and I like monitors!!!!). Either you are struggling to reach the notes that are out of your range, or you are trying to change the timbre of your voice too much. TAKE EACH TUNE AND MAKE IT YOUR OWN!!!!!!!!!.
If you are crippled without monitors, you are in trouble. Bad monitors can sometimes be worse than no monitor. When you can hear the house enough to determine pitch here and there you'll be ok.(if the system doesn't suck).
Huge advice for karaoke singers especially rock/pop........GO TO U TUBE....yes I said that dirty word, find multiple
LIVE versions of your song. That will provide a more
realistic version of what you can actually sing. Many of those singers CANT reproduce their own studio versions live either..
You may be struggling to execute something live the original singer can't either.
Metallica is a good example, he's not screaming as much live. In the studio he can because he doesn't have to sing for a few days after.
Some songs are in E but always played live in Eb because the singer cant hit the notes every night. Iron maiden has even gone down to D live (And Dickensen is amazing!!!). Some singers sound awful and thin live without a studio double track, and others won't even do the studio version (Breaking Benjamin "Enjoy the silence") cuz they probably can't. Some don't sound right live without all the background vocals. Scorpions is a good example as many high notes actually came from the now resigned guitarist.
Look at those live versions, as many as you can find before trying to kill yourself to execute the impossible.
In my experience: The audience will enjoy a good performance, are more happy to hear a song they like even if its not perfect, over a static lifeless perfect pitch execution. It's YOU breathing life into a song that matters, not your perfection or ability to clone someone else perfectly.
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Purple Frog Karaoke Cuz we all feel odd and love to "croak"