First of all, learning to play by ear generally means that you need to be able to hear pitch and gage the quality of chords with your ear. In other words you would need to be able to distinguish the difference between major and minor chords, dominant and diminished etc. The only problem is most people do not possess an ear capable of such distinctions.

I've been playing the piano for 36 years and I often cannot tell the difference between chords. How is someone with no experience supposed to do this? Does this mean that my ear isn't any good? Quite the contrary, I have very good relative pitch and can often hear entire chord progressions but often miss the nuances of each specific chord. Therefore an approach which is solely geared to hearing the changes has its limitations.

The other problem with learning by ear is that you cannot gain a complete understanding of music just by listening. You see, music is like math. It has formative structure derived from centuries of musicians and teachers who have dedicated their lives to the understanding a betterment of each specific musical genre. To discount this process and work around it using just your ear is counter productive.

For example; let's say you're going to learn to play the blues. If you learn by ear that would mean you would have to hear not only the dominant seventh chords, then the melody which is derived from the blues scale, the rhythm which comes from structured meter and the re-harmonization of the chord structure all without understanding the words I just said. It would mean you would have to hear all of this without knowing what its called, how it works and how it all comes together. You would learn by watching someone else play the piano, copy it and repeat it until it sounds the same as what you just hear.

Not only is this a completely inefficient way of learning it is highly limited because you cannot gain an understanding of what it is you're actually doing. Only until you are able to comprehend and dissect each specific aspect of the music can you fully appreciate and learn from it.

I believe that it's highly productive to learn how music is formulated rather than just hearing it and trying to repeat it. Why? Because that way you can stretch the boundaries of learning and be able to move your playing to another level. Even if you were able to copy certain aspects of learning to play by ear that would severely limit you from moving beyond that point because you simply cannot understand what it is you're doing.

It would be like trying to build a house with no foundation. Eventually if you wanted to add an extra floor of musical knowledge your paper thin layer of foundation and understanding couldn't possibly support it.

So, what's a better way to learn? Choose a teacher or online piano lessons that can help you build a strong foundation. In other words, pick a course that helps you with the basic understanding of how music works. Then you can use your ear to strengthen your understanding because the ear can converse with the mind and come to a consensus of how and why things sound the way they do.

Where do you start? Start with how chords and scales are made and use that information to formulate melody and structure. Your ear can support this process obviously but it's the scales and chords that create the building blocks of true musical understanding.

It's not enough to know how to play a simple F, G, C progression with melody. You need to know why and how this progression works and why it sounds the way it does. Then and only then can you begin to build on that foundation by learning richer chords, re-harmonization and more complicated melodies.

For example; F, G, C can sound so much better if you play it as Fmaj7, D-7, G7, Db7, Cmaj7. This is the same chord progression but re-harmonized to sound richer and more pleasing to the ear. How can you possibly do this if you use only your ear? For the vast majority of people who want to learn to play the piano it's impossible. So, next time you're thinking of learning just by ear, you might want to reconsider that plan. Why limit yourself?