The Basics of Reading Chord Symbols
In contrast to the strict, prewritten notes of classical sheet music, lead sheets allow the musician more freedom by limiting its notation to chord symbols (letters above the staff). Lead sheets are commonly found in jazz or gospel music, so if you're a classical musician, this may be the first time you're hearing about them. I remember the first time I saw a lead sheet during a rehearsal: "Where are the notes, what do I even play?" I thought to myself in panic. These letters may appear confusing at first, but once you understand how to read them, you'll be able to play a much wider range of music.
As you can see, this sheet music has nothing but a melody and chord symbols. In this case, it is your job as the pianist to "comp," or accompany, the chords as you see fit. If you're playing this song in a group setting, you won't need to worry about playing every note of the melody either.
The simplest way to comp these chords is to play the root of the chord as an octave with the left hand while you play some inversion of the chord with the right hand. For example, after the the N.C., or "No Chord," in the pickup measure, the first chord symbol we see is C. With the method we just discussed, you would play something like this:
Of course, if you play all the chords with this voicing, you will quickly find that you're jumping around the keyboard a lot. That's why it's important to use voice leading to figure out the right harmonic progression for each piece of music. Try out different inversions for each chord to see which provides the smoothest transition from one chord to the next.
With the right voice leading, you can keep the melody clear by playing it as the top note of every chord. You will also sound more put together, since jumping large intervals can produce a choppy sound overall. This takes practice and experience, but over time, you'll learn how to use your chords to accentuate a piece's melody and create intricate harmonic progressions.
Here's one way I would voice the example from above:
Notice how the right hand chords are consistently voiced with the melody notes, and the left hand keeps the note C on top of the chords for almost three measures. Even for the D minor chord, this C works because it is the seventh of the chord (creating a minor seventh chord, as discussed in a previous post). Also, in measure three to five, the quarter notes in the right hand act as passing tones to the next chord. All of these aspects contribute to a cohesive sound throughout the otherwise "jumpy" chord progression.
Many jazz musicians find that these chord symbols are more liberating than prewritten music, since they offer the freedom to play whatever sounds right within the key of that chord. Likewise, you should also take the opportunity to improvise and experiment with different voicings as you learn to embrace this type of sheet music. Have fun with it!