Tony, first off let me compliment you on being able to sight read quickly and accurately. It is definitely not a disability. What is important is a good sense of tempo to be able to set the groove and stay in the pocket. Playing by “ear” although is a slightly different kettle of fish. The approach to ear playing is the same as sight reading, learn it in small increments, and repetition. That is what you did many years ago learning to sight read, you may have forgotten. Problem is the older we get there is resistance to repetitive practice. . My sight reading is only average, playing my own arranged songs by ear is pretty good and playing the changes is pretty good. For example I have to learn 4 methods of playing the Tennessee Waltz. Version one is our swing band arrangement as a jazz waltz, and I have to read that one if it is put into a dance program. The second version is my own arrangement if I do it as a single performer. I play it as a slow waltz with my own chord embellishments. The third version is if I play it as a country tune in conjuction with other players. Then I usually just play basic chords. The fourth version is backing other singers at a jam. I have to play the song in their various keys, different tempos, and be ready to anticipate where their next chord is going to or if there is a change in phrasing. What I am trying to say here is that this is a lot of times to play the Tennessee Waltz. That is a lot of repetition, repetition.
As I stated in an earlier post, when I learn a song by ear, I usually focus on learning the melody, singing it acapella even if it is an instrumental. Play one chord, sing 1,2, 3 or more bars. Repeat. Seriously, start with “Mary Had A Little Lamb”, play first chord and sing until the next chord change. Play the next chord and so on. I am confident you can do that. Baby steps! Move on to more difficult songs. If not sure of the chord listen for the bass line, generally that will give you the root of the chord. You have an advantage over the people that can only play by ear, is that they need to hear the melody before they can learn the song. They can’t hear it off a piece of sheet music. Just remember baby steps. DennisD
PS just noticed rharv and bob covered some of this

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