Watch the 7(no3) Arpeggio online guitar lesson by Brad Carlton from Guitar Lab: Diamond Rock Rhythm
This lesson deals with the 7 no 3 arpeggio. Diagram two shows how this arpeggio can be viewed as the power chord with the addition of the b7. By viewing it this way, you can learn to hear the tonal quality of the b7 quite easily. It is important to reference the b7 two different ways: it will always be a major second (one whole step) lower than the root, and a minor third (three half steps) higher than the 5.
I will demonstrate this 7 no 3 arpeggio in both rhythm and lead guitar playing situations.