As "musicians" it has been my experience that "ear-players" are even worse musical whores than "vocalists."
The "EAR PLAYER" expects EVERYONE else in the performance to be so well versed that all others will adapt to to their LIMITED KEY.
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Ear
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Twelve keys BY EAR!!!!
A "true musician" can conform to the needs of any vocalist. Vocal - is the only gift granted by GOD.