Learning to Play By Ear
Playing by ear is a useful skill for any musician of any age. It shouldn't be used as a crutch but when paired with other aspects of music such as theory and instrument practice, the effects serve to augment every student's music learning experience. Not only this, but it's a great feeling to be able to play whatever you want, whenever you want!
Developing your ear to hear melodies and harmonies well enough to play them back can be a daunting task. There is no truly easy way but the best way to start would be to, well... do it! Of course it's easier said than done, but the more you work on this skill, the easier it will get. Here are a couple of ideas to get you started:
1. Start with a single melody line: Picking out melodies and harmonies can be overwhelming at first. Pick a song that is simple that perhaps you know how to sing (the simpler the better, ex. a nursery song.) Try matching the first pitch of the song to your instrument. This can take a little guesswork, but again, the more you do it, the easier it will get.
2. Use scales: Does your melody move up or down the notes of a scale (step-wise motion) or are there skips? Listen carefully; if the motion is step-wise, chances are figuring it out on your instrument will be a little easier than if there are a lot of skips because the notes will be right next to each other.
3. Use chords: This is where knowing music theory will help greatly. When identifying harmonies try your best to hear if the chord is minor or major, this will be a good starting point. The next step would be to identify the lowest note of the chord and to try building notes on top of the first one. Remember that chords can be in inversions, leading to tricky chords to figure out. If you can figure out at least the root position of the chord in question, you're off to a good start! Listening to the bass line of a piece will also aid in this. This is perhaps the hardest part of figuring out a tune, so don't get discouraged!
4. Sing: If you can sing the tune after hearing it, you're already on your way! Try matching the pitch of your voice to the corresponding note of your instrument. The more scales and arpeggios you can sing, the better chance you have of identifying the correct notes and harmonies!