Rock Revolution

In the upper-right hand corner of the screen, there is a meter that looks like an equalizer. This is the Atmosphere Meter, which acts like a Rock Meter would in Guitar Hero/Rock Band. Once the Atmosphere Meter is filled, the Power Meter will start filling with more notes. When the Power Meter is full, tilt the guitar or hit the left and rightmost pads on the drums and the bass pedal at the same time to activate the Power Meter. Do this two more times in a single song to unlock the achievement.

Despite the description, you can also get this achievement over multiple songs in a gig. I used the Rock Band Fender Stratocaster guitar and needed to hit the Back button instead of tilting the guitar to activate the power meter. I hit the back button twice during the first song of the gig and once during the second song to get the acheivement.