If you are a fan of modern metal, your favourite players use a number of "wrong" notes (that is, notes that are not in any scale you can recognize) and yet they sound great! How do they do it?
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".
The wrong way to go is to search for a book titled "42 Ways To Use Outside Notes", or similar. I have seen time and again with my student that when learning this kind of skills less is more: you need one good trick, and then you need to master it - and at the same time you will train your ear to understand the "outside notes". If instead you learn 42 tricks, you will not focus in mastering any of them, and ultimately you will not be able to play better.
In the video below I explain one of the simplest and yet most effective way to use outside notes in a Metal solo. Sure, it is not the only possible trick (the video would be hours long), but it's a great first trick to master and you will get a surprising mileage out of it. Watch the video now.
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!
Tommaso Zillio is a professional prog rock/metal guitarist and composer based in Edmonton, AB, Canada.
Tommaso is currently working on an instrumental CD, and an instructional series on fretboard visualization and exotic scales. He is your go-to guy for any and all music theory-related questions.