Guitar Capo
A guitar capo [capo = cap = head] is a clamp that is used on the guitar to make the neck shorter. By placing a capo (head) on a particular fret, you create a 'new nut'; a new zero fret.
A capo can be used on the fretboard for any tuning. The really cool thing about them, is that your guitar has 'sweet spots'. When you place a capo, say, on the 3rd fret, & play in G, your guitar resonance might 'light up.' Listen for the sweet spots, while exploring different keys.
Make sure when you are placing a capo, that it is straight, & makes good contact with the fret (evenly). You can get 'buzzing' if the capo is not set well.
When you place a guitar capo at a certain fret, & play the chords of a given key, you are actually playing in a new key.
If your jamming with other people, & recognize the key they are playing in, you can reinforce - thicken it up, expand - a harmonic rhythm with brilliance, by using the capo up high, while fingering a different key.
A capo isn't mandatory, since your fingers do a similar thing as a capo when you are fretting higher versions of chords. The capo does make things easier, & gets some great sounds & mileage for the chords you already use (ie. C, G, D, A, F, E, etc.).
Capo Chart for Sharp Keys
These are the keys that sound when we place a capo on frets 1 - 9 while fretting the sharp keys. C is neither a sharp nor flat key.
Capo Chart for Flat Keys
These are the keys when we place a capo on frets 1 - 9 while fretting the flat keys. C is neither a sharp nor flat key.
Chords in Keys
A key is a tonal center - all other derived tones circle around key tone as the center [the home tone]. Our ear rests on this tone.
The diatonic chords (derived tones & chords within a key - across the tones of a key center) are the 'expected' chords when you are playing or writing a song in a particular key center.
The first set of diatonic chords that we learn in every key are triads. Triads are 3 tone chords built by superimposing intervals of 3rds (from the tones of the key - every tone in the key, the scale, can be a root of a chord). The qualities derived from a Major key center are I IV V Major; ii iii vi minor, & vii diminished. When you have the triads in your hands, add the 7 to each chord. Examples in C: Triads | 7ths.
Often within a song, nondiatonic tones & chords can be used for interest, tension, & voice leading. Check out this harmonic map.
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