Accompaniment from Thorough-Bass

Accompaniment from Thorough-Bass

Well, after spending a few months working on reading skills, we are ready to mount the next step on the road to Parnassus. Reading open score in C clefs is all well and good, but it is mostly a passive process. We observe without understanding. Now we start learning the 'why' of musical construction and even injecting a little bit of creativity. 

We will be looking at three different subjects really: the broad study of Harmony, Keyboard Harmonization, and Figured Bass. We'll be delving into the latter today.

Composers phone numbers were shorter back then.

To any of you who haven't taken any music theory courses, a figured bass is just a bass line with assorted numbers below each note. The numbers are intervals and describe what notes should appear above the bass, though not in what order. These numbers combined with a bass note will tell you what kind of chord to be played above it. Think of it like baroque lead sheet symbols. Instead of listing a G/D above the notes, they would write a D with the numbers 6-4 underneath. Now, it lies beyond the scope of this post to explain how to read Figured Bass, so if you want to learn more, I suggest buying a music theory textbook, or even a book concerned with Figured Bass. 

Speaking of books, I've collected a few on the subject and have been flipping through them for a while to figure out how to become adept at accompanying from a Figured Bass (also called a Thorough-Bass, or a Continuo line).

•  I have a slim volume by Helen Keaney that has some handy idiomatic progressions and helpful hints.
• There's also the two volume set by Morris that treats the subject more as 'Learning Harmony at the keyboard.' 
• For authenticity, there's the Essay on the True Art of Playing Keyboard Instruments by C.P.E. Bach, of which a great deal of the book is concerned with the ins and outs of proper continuo playing. 
• There's the Keller book which is straight and to the point with many basses drawn from the literature.
• And for the ultimate comprehensive resource, all other books pay homage to Arnold's sprawling two volume treatment of the subject, charting the history of the practice as well as the specifics of how to realize basses.

After consulting these books and few others that mention the subject, I've extracted some words of wisdom in working in the subjects of Harmony, Harmonization, and Accompaniment from a Thorough-Bass:

1. Remember that "'to know' of itself is little virtue; you must be able 'to do' as well." Proctor, in his book on Harmonization at the Keyboard, reminds me that while I 'know how' to play the violin, it does not make me a violinist of any sort. A proper musician must be able to do something in most any situation. This is one of the guiding principles behind the AGO Examinations. I know how to improvise on the organ, but I haven't trained sufficiently to be able to do it whenever the need arises. In the study of harmonizing melodies and playing from Figured Bass, 'looking at examples will not suffice; there is a muscular memory involved, and that, as well as the mental memory will have to be exercised.'
2. Remember what Aristotle said about the difference between brute beasts and human beings; he said that the main difference is that human beings have a 'conception of the result to be produced, before the realization in the material.' Arnold calls this important faculty the 'hearing mentally the music read by the eye.' As I've mentioned before, and most of these authors affirm, we must know how the solution will sound before we have played it. In the same fashion Michelangelo took a block of granite and chipped away the extra material to reveal the finished forms that waited beneath.
3. Arnold says, "Hand in hand with the above mental apprehension of combined sound, it is of the first importance to develop a quick and almost automatic response to the mental impression derived through the eye." In learning Figured Bass playing, we will be learning about harmony, but we will also be learning to associate figures with chord shapes as well as the tactile sensation of those progressions.

So what's the plan?

Our first step in learning how to Accompany from Thorough-Bass is to become familiar with the 'vocabulary', that is, the figures and what they imply. There are 7 fundamental types of chords to start with: Triads (and their two inversions), and Seventh Chords (and their three inversions).

Now, I recall from my college days one of my theory professors telling the class that the number of combinations of the notes C, E, and G on the keyboard numbered in the quadrillions. I don't know if that's true, but in any case it is a lot. To narrow this down, we will limit our spellings to those that can be easily be played by two hands. To narrow it even further, we will begin our Figured Bass studies by placing the bass note in the left hand, and the other three notes (always 4 voice harmony, by the way) in the right hand in close position (in other words, the three notes are within an octave of each other). If this sounds tricky then believe me that it sounds much worse than it really is.

Using this arrangement, there are three ways we can play a C major triad. Assuming C is played in the Bass with the left hand, we can play in the right hand from bottom to top:

• C, E, G (fifth of the chord on top)
• E, G, C (root of the chord on top)
• G, C, E (third of the chord on top)

Each of these arrangements produces a kind of shape. These 'hand shapes' should be memorized and internalized until they are totally automatic. The other thing we must pay attention to is the interval between the top of these shapes and the Bass. In the first arrangement, the top note is a 5th (or an octave and a 5th, or two octaves and a fifth) above the bass. If you try to use this shape a 6th above the bass, then surprise! You now have a 6-4-2 chord instead; useful if you're trying to make the third inversion of a seventh chord, but rubbish for the simple triad.

This will take time and experience, but this actually is a shortcut. If you learn these 'hand shapes' and at which intervals they are used to produce the chords described by certain figures, then the complicated problems of proper voice leading (remember all those rules from Music Theory which had you staring at your paper for long hours trying to find parallel fifths and octaves?) will largely disappear, and the middle voices will mostly take care of themselves.

Remember though, that we are learning all of this at the keyboard, so we are cultivating practical knowledge as well as muscle memory of the correct positions. Therefore, we must practice these things in all keys, major and minor. A good way to do this is by practicing certain common cadences, and especially sequences. If they can be performed in one key, then move up a half-step and perform them in another, and another, until you have played it in all different keys. Try playing it slowly at first, using your knowledge of Harmony to tell you which chord you are playing (tonic, supertonic, mediant, subdominant, dominant, submediant, or leading tone). Then play it quicker and feel the muscle memory take over as you anticipate the sound that will be created and let your hands recreate that sound on the keyboard.

Morris' book on Figured Harmony at the Keyboard is a handy resource since it has common cadences, sequences, and exercises for each figure.

I'll leave it at that for now, but I'll be revisiting the topic as things progress.