Claim a 30% off ToneGym coupon here: Sign up for ToneGym:. My video on why guitars are not "in tune":. Power chords, or fifth chords, are a staple of guitar music. Regardless of the easy sound and shape, there is a lot to talk about when it pertains to fifth chords, with even their classifcation as 'chords' up for dispute! And, an extra special thanks goes to Peter Keller, Douglas Lind, Vidad Flowers, Ivan…