Moving the Boxes - A Guide to Transposition and Scale Selection
So you know all the boxes in a C major scale because that's what was in your theory book, but you need to write a solo in A. What do you do? How do you apply all of your scale knowledge to writing in a particular key? How do you take something written by someone else and change its key? In this lesson we will look at how to do all of the above.
For the record, transposing means changing the key of a sequence of notes without affecting their harmonic relationship - we will look into that as it is closely related to scale selection and moving boxes around the neck to get the scale you want.
The most important concept to grasp in all of this is that of the root notes of a scale. When we talk about a scale of D major, or A minor Pentatonic, the scale is named for the root note - D, or A in the two examples I just gave. The root note is always the first note played in a scale when practicing it, and it is the note that gives a scale its basic identity. In this lesson I talk a lot about scales and keys - they are really pretty much the same thing. Playing in a particular key means using the notes from the scale associated with (and named for) that key. Of course this isn't a hard and fast rule, but it is a good starting guideline.
Moving back to D Major - here are a couple of examples of different fingerings for it. You may recall from reading about CAGED, that there are five different major scale variations in total, and the same number for the pentatonic scales. (If CAGED is new to you, check out my lessons here).
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Although these scales are equivalent, they use a different selection of notes - always the notes in the scale, but moving to higher versions as we move up the fret board. How do we match these scales together and understand how to use different boxes to get the scales we need? We use the root notes. The root notes in both of these scales are picked out in green. As you can see, these two scales overlap a few of the notes as they are pretty close together on the neck. When we are playing within a scale, we always play relative to the root notes. So, if you have a tune in mind, and it starts on the 3rd of the scale, you can play it in a couple of places in each of the 2 scales shown above, giving you four choices of where to start. Just start at one of the root notes, and count up to the 3rd (that's 2 steps up from the root). To make it easier I have picked the 3rds out in red.
The important point here is that you use the root note as your signpost to understand how the boxes fit together, and to locate yourself within the scale. A couple of the choices above will be an octave (8 notes) higher than the others - being an octave higher makes no difference to the musical relationship of the notes, but will make the melody sound in a higher register - this may or may not be the effect you are looking for, but this gives you extra options.
What else can root notes do for us? They are essential for correct scale selection.
By Scale selection I mean two complementary things. The first is ensuring that you are in the right key for the piece of music that you are playing. The second is picking the right scale from your selection of 5 shapes to get the musical effect you are looking for.
Firstly, picking the right key - this is extremely important, and root notes are essential for this. In order to pick the right family of scales, you first need to know what key you are in. I'll use major scales as an example. If your band is playing a song in the key of A major, and are currently looking at you expecting you to rip into a solo, the first thing you need to do is figure out where each of the A major scales is. Root notes are your signpost here, but you must also have a good knowledge of the notes on the guitar to help you conduct your search. Using your knowledge of notes on the guitar, locate one or more of the root notes - using the bass strings is best for this. OK, I'm thinking of the A on fret 5 of the low E string. If you have studied your CAGED scales, you will know that both the E and G shapes feature root notes on the 6th string. Now, if you pick one of those shapes, say the E shape, and align the root note of the E shape scale with the A note you have identified, you have now figured out how to play your scale of A major.
Next, you need to select which of the 5 scales you want to actually play in. When you have located the CAGED E shape, you can use the rules of the CAGED system to go up and down the neck, picking equivalent scales until you find one you like. Its up to you - do you want a low solo, or a high solo? If you have practiced CAGED a lot, you should be able to move between the boxes without thinking about it - maybe starting low, and moving up to a crescendo on the higher notes - at this stage its up to you!
Of course, you may want to go about this backwards, and write a tune then figure out the key. In that case, you have already selected the scale - you just need to figure out what your root note is, what the type of scale is then you have your key!
Learn Boxes Not Fret Positions
As guitar players, we're pretty fortunate. Not only do we play the most amazingly expressive instrument there is (what other instrument can go from Segovia to George Benson to BB King to Rusty Cooley?), but we also have it easy when it comes to key changes. If you play the piano, or clarinet, you have to learn exact and different fingerings for each scale in each key. For the guitar, you need to learn a box, and the slide it up and down to get different keys - then you can add boxes to get more flexibility.
A mistake that some beginners make, when learning their first scale, is to learn the fret numbers instead of the relationship between the notes. For instance, A minor Pentatonic is:
6th string 5th fret, 6th string 8th fret,
5th string 5th fret, 5th string 7th fret ...
That works to learn that particular scale but can lead to confusion when later trying to play for instance a G minor pentatonic - you need to learn a completely new set of fret numbers - just like our piano player did. The trick here is to remember the root note and the relationship between the notes, not the actual frets they are played on.
A good tip when you start learning scales, is to always start on the root note. Most scales played on the guitar have a few notes left over below the root note on the lower strings, and above the root note on the higher strings. I have picked these notes out in blue in the 2 diagrams above. To start, you can ignore these, and learn scales starting from the root note, ending at the next, memorising the relationship between the notes, not their actual fret positions. For some scales (for instance the CAGED G shape shown above) you can do 2 full octaves and end up on a root note. If you memorise the shape rather then the fret positions, when it becomes time to move from an Am to Gm, you just slide everything down 2 frets, and play the same pattern - much easier! So think of your pentatonic scale like this:
Root note on the E string, 3 notes up on the E string
Same fret as the root note on the A string, 2 frets up on the E string ...
OK, our next challenge as guitar players - your band is really happy with your ripping guitar solo in A major, but the singer is complaining that he can't sing the song that high. Is it OK if we change the key to G major? That's great for the singer but now we have to figure out a couple of important things. First, how do we change the chords to match, second how do we change our solo to match?
Lets look at a little theory first. What the singer has done is ask us to transpose the song down by two semitones which is the difference between the notes of A and G. The only real rule here, and its a simple one, is that to transpose a piece of music, you just move every note in the piece down by exactly the same amount, in this case 2 semitones. For those of you who have read my lesson on intervals, here, we are transposing down a Major Second. As long as we move everything by the same amount, the relationship between all of the notes, including all of the notes in the chords remains identical. We will be playing in a different key, but that is all that will change. If we were in a major key before we will still be in a major key. the chords although based different notes will stay major or minor or whatever they originally were.
So the first trick is to work out the number of semitones up or down we need to move to hit the key we want. Another trick to note is that you can go up as well as down to reach the new key. Moving 2 semitones down is the same as moving 10 semitones up in terms of the key you will be playing with. Why is this? Well there are 12 semitones in an octave, and in the example I just gave, 10 semitones up, is an octave higher than 2 semitones down - (10 + 2 = 12) - and musically, different octaves are identical in terms of the functions of the notes. Now obviously one of those options will sound better than the other for the song you are playing so you have to be sensitive to the effect you are trying to get.
Sounds simple enough, but how do we put this into practice? First, lets look at the chords. Since we were originally playing in A major, its a safe bet that we were using the chord of A somewhere. Lets assume we are also using the chords of D and E, as they are commonly used in the key of A, being the 4th and 5th of the scale. To transpose to the key of G, we just change the chords so that they are down 2 semitones. So, A becomes G (why is that? Well, there are 8 notes in a major scale, and when naming them we use A through G then go back to A again - so the note below A is G!). Also, D becomes C, and E becomes D. Just substitute the new chords for the old and bingo, you are playing in a different key. If you are having trouble with this, it is also worth looking at a couple of other lessons, Major Scales 101 here, and Degrees of the scale here.
OK, now for the notes. Well again, this is as simple as just adding or subtracting semitones from the note you were originally playing. If you were playing the note of A, you change it to the note of G, and do this for each individual note throughout the song subtracting the same number of tones. Now, that is usually fairly easy, and you can mostly do this just by moving each note down 2 frets, but if you end up with open strings and you want to subtract tones, you have to compensate by moving to a lower string. At this stage you need to think about switching to a different scale shape that has some higher notes in it - you need to jump up an octave. At this point you can use your knowledge of root notes to move to an equivalent scale in a different position that works better. Continue doing the subtraction, but substitute the note that you have figured out for the same note in your new scale position.
Lets look at an example. It turns out that the song you were playing originally in A was happy birthday, and it looked like this on a tab:
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Now we have transposed it to G it looks like this:
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Note that the chords have been substituted as we discussed, and if you check the notes on the tab, you'll see that they have all moved down 2 semitones, but the fingering has been adjusted to make this work out OK. Spend some time and compare the 2 tabs to understand how the notes differ and you will be well on the way to understanding transposition. We have also changed the key signature to compensate (if you don;t know about key signatures, you could check my lesson on finding the key of a song here, and we'll do a more in depth lesson on key signatures in the future.
Now, if plodding through the whole song subtracting a couple of semitones from each note sounds long winded, that is because it is. I wanted you to understand the principles first, but there is an easier way to approach this. It depends on knowing all your scales, and takes a lot of practice. The trick that more experienced guitarists use is not to learn specific notes, but to learn a tune or solo as a collection of notes within the context of the scale boxes. Once you do that, you are freed from the context of a particular key, and to make your 2 semitone shift all you have to do is move your whole box down 2 semitones and play the same pattern. Using this technique a practiced musician can transpose a whole tune with little thought as he goes along. He will be able to tell you the notes if you ask him, but he is not doing that subtraction in his head as he goes along, he is thinking in terms of patterns and shifting down the neck.
This works pretty well most of the time, but you can run into trouble if you need to switch your solo too low, and you end up moving below open strings. An even more flexible technique is to start thinking of the song in terms of intervals relating to the root note. If you do that, not only do you have the flexibility to move boxes up and down the neck, but as and when required, you can move to a completely different scale shape, and play the same notes just by working with the same intervals. Again, good guitarists can do this without thinking about it as they go along, and once again, root notes are very important here.
As usual, the key to all of this is practice. You need to know your scales inside out, and all of the notes within them. Know all the variations of the scales so you have the maximum number of options for transposing, and practice changing keys of songs initially by hand until you understand the principles well enough to start doing it as you play.
That's the end of the lesson - as usual if you have any questions or comments, I'll see you on the forum!