I usually don't have pitch issues when recording, but on occasion I do. I've tried using just one ear piece on the headphones, but on this particular song, still had trouble. Can you explain the science behind finding pitch when using headphones?
First of all, I hope you mean you just took 1/2 of that one ear off when using headphones. I do not find that taking a whole ear off will not help you. To clarify, take one closed headphone (not "open" headphones... ones used in the studio are usually closed to avoid feedback) and slide it half off your ear. It should cling to your head in such a way as to avoid feeding back to the mic.
Rarely, I will come upon a singer who does better with both "cans" on, but by far most singers do best with one earpiece half off. You'll also find that you'll favor one ear over the other for this maneuver. Experiment to see what works best for you. Try the left ear, then the right ear half off.
Lastly... DO NOT hold your cans with your hands. This will cause your arms to weigh down your ribcage. Instead, raise your hands above your waist and either "talk with them" or press fingertips into each other to open your chest, stay tall and flexible.
For the best discussion on the "science" of headphones and hearing pitch, see this link. You'll see I've contributed my two cents to the discussion, too.
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