About the E7 chord
To play E dominant 7th, use the first shape above. Place your index finger on the 1st fret of the G string, your middle finger on the 2nd fret of the C string, and your ring finger on the 2nd fret of the A string. Leave the E string open. Strum all four strings and check that each one rings cleanly.
Root
E
Quality
Dominant 7th
Notes
E · G# · B · D
How the E7 chord works
E
Root(1)
The home note. It gives the chord its name.
G#
Major third(3)
The major-third interval that establishes the chord's major base.
B
Perfect fifth(5)
Adds strength and stability.
D
Minor seventh(♭7)
Adds the defining minor-seventh color.