These answers are unhelpful and inaccurate.
Although many great musicians do find it easy to quickly play songs by ear, there are many more who found it difficult and had to practice before they could do it quickly.
For most musicians the two big factors in how long it takes to play a song by ear are:
- How complex the song is.
A simple 3-chord song played on solo guitar will be easier to figure out by ear than a full band arrangement of an avant-garde jazz piece!
- How practiced the musician is at playing by ear.
Playing music by ear is a learnable skill, which depends on a range of listening skills each of which you can improve through ear training. Once you have these core listening skills you must still take the time to practice playing by ear if you want to be good at it.
How You Learn To Play By Ear
When you first begin learning to play by ear you will find it slow-going. It may take you a few minutes to work out even a line or two of the main melody, as you use trial-and-error experimentation and rely on your ears simply to tell you when you’ve got notes right or wrong.
As you train your ears (for things like intervals, chords and progressions) and improve your sense of relative pitch and rhythm, and practice working out music by ear, you will find yourself increasingly getting the notes and chords right rather than wrong.
What began as a slow (and sometimes frustrating) experimental approach can quickly transform into an imperfect bu