Improvisation
"My intended audience is anyone who wants to take their improvisation to the next level. A little background in music is required to know all the terms I use concerning musical rudiments like scales and chords. As my experience is primarily piano-related, this is the instrument I will refer to, though the concepts in this article can be applied to any instrument.
Please, if you want further help or advice learning to improvise do not hesitate to contact me, Derek Andrews. I can be reached at zomcoder@hotmail.com and AterMelodius on AIM."
The Psychology of Improvisation
One of the main reasons many people do not improvise is totally psychological. They say of themselves "I cannot do it," and as such give up before they even try.
It is probably the most common in pianists who already have a developed technique. However since they have not played to make their physical vocabulary flexible, they might be under the mistaken impression that they "cannot" improvise. In actual fact, improvisation is a new skill that an already experienced pianist must build from the ground up, with the patience of a beginner. Once you have started simply noodling in a given scale, or made up some simple melodic fragment or other of your own, no matter how simple, you have begun improvising. All you must do beyond that is work at it and expand your vocabulary.
Freeing one's mind of inhibition is also important every time one sits down to improvise. If one tries to force one's playing to have a particular sound or figure, you are not trusting in the spontaneous impulse. When you truly let go, your music can "take off." It takes a long time to build a vocabulary which is flexible enough for this to happen, but it is well worth it and incredibly satisfying when it does happen. It feels as though something else takes over when you reach this state.
There's nothing wrong with improvising to practice a technique, of course. This may be what you primarily do in your early stages. Though your improvisation may not take flight quite as intensely as it will later on, it is still always satisfying and fulfilling to be creating your own music.
Finally, another obstacle which prevents people from improvising is a fear of rules. Western music has a habit of making a big deal out of the part writing rules, chord progressions, and forms of the past. Today, an improviser influenced by the Western tradition might be worried he is hitting wrong notes or using incorrect progressions.
The truth is, there is no such thing as a wrong note or something incorrect in music. All is freedom. Once you gain enough experience, you may or may not find it amusing to consciously absorb part writing rules into your playing, but there is no cosmic law which says you must do so and it is quite debatable whether these things actually make music better or not. They originated as guidelines for writing for 4 voices, not the piano, after all.
The bottom line of the Psychology of Improvisation is "don't worry, if it sounds good, it is."
The Basics
Improvisation is largely dependent on developing a large and flexible physical vocabulary. That is, a flexible vocabulary will allow the improviser to use thousands of different figurations, chords, rhythms, and harmonies almost without thinking about it, in any position or inversion, in any musical situation that might come up. This is not quite so daunting as it sounds.
Learn all 24 Keys
As you improvise, make sure to learn to play in as many different keys and positions as possible. That is, invent an interesting figure that is more jagged or melodically interesting than a plain scale, and then try playing it in different keys. If you haven't played in a particular key before this will feel uncomfortable initially, but stick with it as it won't take as long as you might think to absorb new keys and positions.
Acquire a Basic Vocabulary of Figuration
The simplest sort of improvisation is homophonic, consisting primarily of chords in the left hand and melodies in the right. Learn to be able to noodle with your right hand while playing chords rhythmically in the left hand. Try breaking these chords up into arpeggio patterns or alberti bass as well. When you're used to playing these basic patterns, try breaking them up in more interesting ways.
Acquire a Basic Vocabulary of Harmony (Chord Progressions)
As you are learning all 24 keys and their constituent chords, you may wonder what some effective chord progressions might be. When you first start out, using the first, fourth, and fifth chords of any key can provide a lot of variety. Eventually however you will want to experiment with more extended chord progressions.
Record Yourself
Even if your improvisation is in its infancy, recording yourself and listening to these recordings is very instructive. When you're starting out it is difficult to remember things that you played even a couple of seconds ago. A recording will allow you to hear what you played that you really liked, and you'll be able to pick out what you played without too much trouble and reenforce it. This occurrs simply by listening to your recordings, as well. Your musical memory will improve with time.
Advanced Tips
The Creative Feedback Loop
One of the ways in which I think about improvisation is like a feedback loop. I begin playing with some familiar harmony, figure, etc. and then I introduce some chaos. I change direction melodically or change rhythm randomly, but I pay attention to what I've introduced, and use it as the basis for what comes next. In this way, I respond to the randomness that I introduce into my playing. It is like a "feedback loop." So in a sense, I never think out anything before hand. Maybe this could work for you, maybe not.
Contrapuntal Improvisation
Once you are familiar with simple homophonic improvisation you may want to learn to play with more complex textures, that is you may want to play with several melodies going at once, i.e. improvised counterpoint.
A good way to get started learning to improvise contrapuntally is to play a simple figure in one hand, and then stop that hand while the other hand plays the same figure, perhaps an octave lower, perhaps in a different location in the same scale. As well as this simple call & answer tip, try simply noodling in a single scale with both hands. It will sound alright. Eventually you'll want your call & answer improvisation to "overlap." With time you'll find better ways to make your counterpoint "mesh."
Contrapuntal Improvisation is not limited to Baroque imitation. Take some of the accompaniment figures you've learned and make the bass line move around as though it is its own melody. This sort of technique is very common amongst Classical and Romantic composers.
Polyrhythm
Polyrhythms can really make the independence of melodies stick out in a striking way. This technique is very common in the work of Chopin, Rachmaninov and to an even more striking degree, Scriabin. They can be confusing at first. The easiest polyrhythm to absorb into your improvisational vocabulary is three against two. If necessary, write out some drum beats in Finale or your favorite composition program, and put two beats above a triplet occupying the same space of time, then tap it out.
It is not always necessary to consciously absorb strict polyrhythms. With time, you'll find you can simply "squish" notes into the same space of time with both hands going. You may not know exactly what polyrhythm you are using, but it will still be precise and intuitive as you play them.
Polychords
Combining chords from distant keys can create striking harmonic colors. For example, if you play a C major chord in one hand and an F# major chord in the other, you'll get a strikingly dissonant, yet awesome sounding harmony. You'll find the tones of these chords overlap to produce a very eerie six tone chord. Experiment with other combinations like these and you'll find the amount of harmonic color available to you as an improviser is truly immense.
Smooth and Sudden Modulation
Learn standard modulations as well as sudden, striking ones. Standard modulations involve using a pivot chord shared by the key you are currently playing in and the key you wish to modulate to. Then you prepare a cadence in your destination key and finally resolve in the new key. There is no cosmic law, however, binding you to traditional modulation. Try suddenly changing to a new key. This can produce a very striking and surprising harmonic shift.
Build up your Musical Memory
Try consciously honing the ability to remember what you just played. That is, improvise a melody and some accompaniment (or two melodies in a contrapuntal improvisation), and try playing them again right after you play them. Eventually your ability to memorize what you just played will increase, and you will be able to improvise complete compositions entirely spontaneously.
Conclusions
This article consists mainly of tips and I will be adding to it over time. If you want more information do not hesitate to contact me, as listed above.