A capo can be a guitarist’s best friend, for more than just how much easier it can be to play in familiar and “guitar-friendly” keys. But it can also add frustration and tuning problems when not deployed effectively. To use a capo correctly, it all comes down to placement.
Understanding where to place the capo in order to be in the same key as everyone else is basic, but essential, and it requires at least a working knowledge of the guitar fretboard and how musical keys work. But even guitarists who don’t read music can be successful at sorting this out with these tips:
Musical notes are measured in “steps.” Moving up or down, if every note available was played (like playing all the keys on a piano, white and black), each one would be a “half step” away from the next. Playing all these notes makes a chromatic scale, and the guitar fretboard functions like a chromatic scale. Each fret is a half step, and capo positions are counted in half steps (that’s the simple “math” in this tip).
The musical scale is notated by letters A through G, with sharps (#) and flats (b) in between. There are no other letters, and even some of the sharps and flats overlap, so in all, accounting for overlaps and the two places where there are no sharps or flats between, there are only 12 notes available—chromatic notes (a scale that includes every musical half step). The scale can then be thought of in terms of sharps or flats, but (usually) not both at the same time.
Since the guitar fretboard is chromatic and every fret equals one half step, then understanding how many half steps are between notes makes it possible to determine where to place a capo.
The chromatic scale discussed above encompasses all notes, sharps and/or flats included:
C C# D D# E F F# G G# A A# B C (in sharps)
C Db D Eb E F Gb G Ab A Bb B C (in flats)
Note that there are no sharps or flats (called “accidentals”) between E and F, and between B and C. These notes have only a half step between them, not two (two half steps equal a whole step).
This builds on the understanding of the alphabetic chromatic scale. After determining the song key versus the key you want your chord fingerings to come from, you count up the number of frets to determine capo placement.
Looking at all the notes in the chromatic scale. If the key of the song is F but you want to use D fingerings, D is 3 half-steps lower than F, so place the capo at the 3rd fret. The fingering key must be lower than the song key. If you run out of notes, you can wrap around the scale notes listing and keep adding frets.
One final element is the major scale, a fundamental structure in music. The most basic major scale is in the key of C, because it has no sharps or flats:
C D E F G A B C
No matter what key a song is in, though, the major scale always has this pattern (where 1 = whole step, and ½ = half step):
1 — 1 — ½ — 1 — 1 — 1 — ½
Applied to the C scale:
C — 1 — D — 1 — E — ½ — F — 1 — G — 1 — A — 1 — B — ½ — C
A whole step, then, is equal to two half steps. So if a song is in C and you want to play it in A fingerings, you can determine that A is 1½ steps down from C, or 3 half steps. Place the capo, then, at the third fret.
If all this has your head spinning, there are some great utilities available to help you effectively use a capo:
- Printable: The Musix printable Capo Chart PDF is easy to slip into your guitar case to help you transpose anywhere.
- Web browser: The DeftDigits Capo Calculator makes it easy to choose one or more keys to transpose and provides a chart of what the playing key becomes at each fret.
- Mobile: GuitarCapo+ for iPhone gives you a capo placement calculator (and a whole lot more) in your pocket.
Once the position on the neck has been determined, an important principle for capo success should be followed for best results. And this principle is the same as one taught from the very beginning of guitar instruction: fingering position. To stay in tune and properly get the stings to ring out, you must always play as close to the fret as possible, while not on top of it (staying “behind” the fret). The same is true when using a capo. The capo should be as close to the fret as possible but not on top of it. A common critique of non-adjustable clamp-style capos is that they pull strings out of tune. Sometimes, yes. The pressure can be too much on the strings. But a properly positioned capo, no matter the style, can usually be relied on to keep in tune. Some will sound better than others, but placement is that important!