You know your metal guitar scales like the back of your hand but you have noticed that your guitar heroes sometimes are simply "ignoring" the scale and play seemingly random notes ... and yet they still sound amazing? How is that possible? Well, it's not black magic, it's just a simple application of tension and resolution, and I'm going to show you how. Keep reading. If you play metal guitar, you know (and like) many players that are using notes "outside" of the scale to spice up their playing. Sometimes we refer to their riffs as "atonal" (though the use of this label is controversial for a number of reasons that go beyond the scope of this article). There is a widespread belief that notes out of the scale are "forbidden," but in fact they are perfectly usable, if you know what you are doing ... of course if you don't know how to use the "outside" notes, they will sound dissonant and "wrong" when you play them. At the same time, restricting yourself to only notes in the scale can make your solo sound stiff, uninteresting, and "scalar." I am not going to explain all the possible ways to play outside the scale. First of all, because there are simply too many ways and I don't have enough space in this column:-) Second, because it's much better for you if I explain one simple method, so that you can get used to the sound of the "wrong" notes. Once your ear get used to them, you will be able to come up with more original ways to play outside the scale. In other words, this is not the definitive, ultimate guide to outside notes, but a method to get started and learn how to explore the sound of going out of scale. This is exactly what I'm doing in the video below: I'm explaining one and only one trick, but it's trick that can take your really far if you take the time to master it, and at the same time it's very easy to understand and play. What's not to be loved? Watch the whole video so you can learn it too. As you can see, what I show in the video is quite elementary, yet effective. It will not take any effort for you to implement this trick into your guitar playing, and you will be able to use it immediately. What are you waiting for? Grab your guitar and give it a try! About the Author: Tommaso Zillio is a prog rock guitarist and teacher with a passion for Music Theory applied to Guitar.