After years of paying attention to the notes and not the intervals, I needed a way to break myself of this habit. In other words, when I look at something like this in the treble clef:
I must force myself to see it as a sixth with C as the lower note (or as a sixth with A as the upper note), instead of a C and an A. You may say, "But, Al, what's the difference? C and sixth or C and A -- you still have two things to notice." But there are three advantages.
First Advantage: My "muscle memory" knows what a sixth feels like. That is, my hands can form a sixth without much conscious thought. So, instead of seeking out a C and an A, my hand just forms the right interval, and all I need to do is put it in the right place.
Second Advantage: As I go from one note or chord to the next, using the intervals can be more efficient. For example, for the first two chords here (treble clef):
thinking in intervals is more efficient. For the second chord, instead of thinking "find an E and a G" I can think "keep the top note the same as the last chord, and form a third."
Third Advantage: When the music has switched clef, or has a lot of ledger lines to deal with, thinking in intervals will work better. I am so used to having the lower clef be the bass clef, that when it's not, I have to actively inhibit the note names that come to my head as I play. And when I've got a bunch of ledger lines involved, I don't have time to count them. When using intervals, both of these problems magically disappear.
So, assuming that it's best to notice intervals, how do you learn to do it? For me, I could tell myself "Notice the Intervals, Stupid!" but I'd still tend to think about the individual notes. My teacher would have me say the intervals as I played, "Sixth! Third! Fifth!" but I would still predominantly attend to the notes. This didn't really work. That is, I'd know what a sixth or a seventh looked like, but I didn't have that instant recognition.
I needed a magic wand that would make me forget the note names, so I would have to use intervals. I sometimes wished that I were starting over, didn't know the note names, thus learning intervals.
That wand doesn't exist, but I came up with something almost as good. It's a trick that makes the notes wrong, so that I'm forced to use only intervals.
The trick is to transpose! If I play a piece in a different key than the one in which it's written, the notes are wrong, but the intervals are right. Perfect!
For example, let's say that I play this:
but instead of playing it as written, I play it in the key of C. I will be forced to use intervals only, because all the notes are wrong!
Technically, I do it like this: The first chord has the root as the bottom note and also the top note (F). In the key of C, those notes are C instead of F. In the left hand, I form a third with my fingers to play a C and an E. In the right hand, I form a fourth, playing a G and a C.
Going to the second chord, I notice that in the left hand I'm just going to move that third down one step (a second), and in the right, I'm just going to repeat the lower note.
From the second chord to the third, I notice that in the left hand, the lower note goes down by a second,, and I form a fifth with my fingers. In the right hand, the lower note goes up a step, and I form a third. And so on through the entire hymn.
I've dabbled with this trick off and on, but because I went back to regular old reading, the use of intervals never stuck. So I decided that for one month, I would only play transposed music. That is, no notes, only intervals for a month.
I set three rules:
1. I played at least two hymns per day (I made it easier on myself by working with hymns -- the main purpose here is to notice intervals, and for this, hymns should work as well as other types of music). A big advantage of hymns is that when you play a wrong note it is immediately apparent.
2. I only allowed myself to read notes for the first chord of a line, unless I get into trouble three times. Since each chord depends on the one before it, once you make a mistake, it's hard to recover. I didn't allow myself to recover by reading the notes. Instead, I made myself go back to the beginning of the line and start again. But if I screwed up three times, I allowed myself to cheat until the next line.
3. I allowed myself to play in "easy" keys, since the benefit of the exercise is independent of key. So I usually transposed to C, and if a hymn was in C, I'd transpose to F.
Did It Work?
Yes. Was it a miracle cure? No, but I am now better at attending to intervals rather than notes. In other words, I can more quickly "see" a sixth than I could before. I find myself using intervals even when note transposing.I found that the technique works best when there is one note in a hand that moves less than a fourth. That's usually the case (as it is in all of the chords in the above example). When transposing, I ended up with a system in which I moved a finger to whichever note moved the least, then formed the interval to get the other note. For example, for the left hand in the above example, going from the third chord to the fourth, I would move the lower finger down a second, then form an octave with my fingers.
Note that I got better at playing transposed. It's still a struggle, but my improvement proves that I am faster at seeing intervals. Also, by not going back to regular playing each day, I never erased the gains that I made.
I currently see it like this: working with intervals is another tool in my toolbox. Sometimes it will help my sight-reading, and other times I will use other tools. For example, when thirds move in stepwise motion, as in chords 3-7 in the treble clef of the above example, thinking of intervals is absolutely the way to go. In other instances, it might help more to think of the harmonic structure or notice the notes themselves.
The bigger the interval, the more problematic it is. For example, in the fourth chord of the above example, left hand, I might think "That's an octave. Or is it, let's check, C, C, OK, it's an octave." So I still have work to do.
I still need to remember to use this tool. For example, when under the gun, playing something for my teacher, I'm less likely to use intervals.
I plan to use a refresher course of this, and do another month of intervals-only training again.