Tutorials:Fractal tunes

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Intro
Fractal music and algo-comp may be new to you, as it is to many. If so, this introduction is just for you. If you are already familiar with the field, skip straight to the next section. Or, if you want to explore details of how the tunes are constructed in FTS see Seeds_and_fractals.

Everyone else can read on and find out about fractal music.

The whole tune is based on a small amount of musical material
Fractal tunes belong to a genre known as Algorithmic Composition (or algo-comp). There's a connection with fractal art too, and you could perhaps think of it as a form of musical minimalism - as you get a lot of compositional material from a very small amount of input.

So for instance all the notes in this tune:

http://robertinventor.com/software/tunesmithy/images/tune_as_score.png

are constructed from the four note phrase that begins it - that's the only material used to make the entire tune - which starts as:

0 1 2 0 1 2 3 1 2 3 4 2 0 1 2 0

midi clip

You can probably see or hear how the same basic pattern is used over and over again in each bar (with the step sizes changed a little). It's less immediately obvious, but the way the tune goes up and down from one bar to the next also follows the same pattern, and the pattern is used in a similar fashion at larger and larger scales to build up the entire tune.

The method used to construct the tune is simple (conceptually anyway), yet the tune still has the capacity to surprise, as it repeats at larger and larger time scales. The whole tune never repeats exactly.

If you change the seed and other parameters, the entire tune changes
Perhaps some of you have tried making fractal landscapes, such as the ones you can make using Terragen. Vary the parameters in the program slightly and the whole landscape changes. Tune Smithy lets you work with tunes in a similar fashion.

There are many types of fractal music - generated from the Mandelbrot set for instance. For some sites to visit to get an idea of the range of work that is done in this field, see the Thinks.com Fractal Music page. Most of the tunes you make with Fractal Tune Smithy are based on a musical seed phrase of a few notes, and various parameters that change the way the seed builds up to make a tune, or change the instruments that play it.

The more complex tunes have more parameters, and may have many instruments playing simultaneously. However, they are still based on just a single seed (usually) and a few other settings.

In fact, most of the tunes are what are known as augmentation, or sloth canons, got by playing the same tune simultaneously at many different tempi - and they are related to an intricate visual pattern called the Koch snowflake fractal. If you want to explore these connections, see:

Seeds_and_fractals

Since the tunes are based on such a small amount of actual musical material, then if you change anything, the whole tune changes. Just change one note of the seed and you'll notice the whole tune change.

No musical training is needed
You can make fractal art and fractal landscapes with no previous training as an artist - and the same is true of fractal music. You need no training at all as a musician to make fractal music. Perhaps it may inspire you to learn to compose more conventionally later on. Or if you already are a composer, you may use the fractal tunes in your compositions or use them to make new pieces just as they are.

This section will assume nothing in the way of previous experience of music making or composing. I will try to keep it interesting for the more seasoned musicians and composers too. Algo-comp is new to nearly everyone including many seasoned composers. However, if you are a seasoned composer you will probably want to skip some of the sections.

Fractal Composing
Usually if one improvises or composes a piece of music, you choose which notes to play individually. Many composers use repeating loops nowadays, and the way the loops interact may lead to many surprises, but still, every note of each loop is set individually by the composer.

In algo-comp though, all the notes of the tune are inter-related. You vary a parameter, and the entire tune will change. Normally you can't change the notes individually - except by post editing after the tune is made.onstruction using musical seeds.

If you make something you particularly like, it can be almost impossible to reconstruct it unless you know the parameters that were used to make the tune. Even if you have a midi or audio recording of the tune, it can easily be next to impossible to work out what parameters were used to make it, especially if you use some of the more advanced tune construction options.

So before we start the tutorial, you should know how to save your work in case you make something you particularly like.

How to save your work
To save your work, use File | Save As (Ctrl + A). Be sure to save your work as Tune Smithy Fractal tunes (*.ts). You can save over the old version again at any time using Crl + S.

First exercise, vary the seed
In our first exercise, we investigate the way in which the tune varies as you change the seed.

Select any tune from the drop list of fractal tunes. Now select a seed for one of the other tunes, from the drop list of seeds. Notice how this changes the entire tune for all the instruments.

Now try editing the numbers for the seed. Keep the first number as it is (usually 0) and change one of the other numbers. You can do this while the tune is still playing.

Once more, hear how the entire tune changes even when you change a single note of the seed.

As you will realise, this needs a new way of working. But you can use the material from the fractal tunes more conventionally if you like.

Using fractal tunes in more conventional compositions
If you want to change the tune on a note for note basis, you need to export the tune from FTS. Save it in Midi format, and then use the material as you please in a conventional sequencer. With many of the tunes (any of them not in twelve equal), you may find the result confusing because of the way FTS spreads the notes out across the midi channels to optimise the pitch bends. You can disable this if you use Out | Set Channels for Each Part | Chann = Part. You may want to do this temporarily only, in order to export the tune to midi.

Or record fragments of the tune. You may like to play the tune for a while, record a part which you particularly like, then use it in your own compositions - maybe add a vocal part and other parts to it.

Another approach is to use the fractal tunes as inspiration. This can be a useful method of melodic invention - enter a phrase as the seed, then the way it is transformed may suggest new ideas - maybe it could free up blocks to creativity too :-).

Making fractal tunes
Here though, we'll focus just on the process of making the fractal tunes themselves.

Fractal music work needs a much more experimentalist approach than other types of music making. Don't be afraid to just try out anything. After all it is easy to change things. If you do something that sounds particularly nice, save it for future reference and continue exploring. If you want to go back to a previous stage of the tune you are working on you can undo your changes using Ctrl + Shift + Z (repeatedly if necessary) and redo them using Ctrl + Shift + Y.

If curious about how the tunes are constructed, look at Seeds and fractals for an introduction.

Making seeds for the tunes
You can change the seed for the tune using the mouse with the Bs | Seed as bar charts or Bs | Seed - edit windows.

You can also make new seeds with the Mouse & PC keyboard Player - see [Seeds.htm#Making_new_seeds_for_the_melody  Make new seed ], also from a music keyboard if you have those - see [Seeds.htm#Making_new_seeds_from_midi_keyboard Make new seed from Music Keyboard].

Instruments
Now lets explore instrumentation of the fractal tunes. Choose File | New. Choose a seed from the drop list or make a new one - any seed is fine for this exercise. You'll hear the tune played on a flute voice. Try selecting other instruments from the Voices menu, and hear what the same tune sounds like on various instruments.

Seasoned composers and musicians can skip the next couple of sections - but you don't have to be a trained musician to use Fractal Tune Smithy to make fractal tunes - any more than you need to be a trained artist to make fractal art. Some readers of this help may have never written a piece or even a melody before - if you are a newbie to orchestration - this next section is for you.

A brief introduction to musical instruments and instrumentation for newbies
You'll notice that the Instruments menu is grouped into families. The voices there are the standard ones from the General Midi specification.

As a newbie to composing, you need to think about which instruments to mix together in your pieces.

Some of the main types of instrument include:
 * Percussive instruments such as marimba, glockenspiel etc
 * Plucked instruments such as guitar, harp etc
 * Wind instruments such as flute, trombone etc, and perhaps one could put voice here too
 * String instruments.

Each of these has further subdivisions, for instance, the wind instruments are subdivided into
 * Woodwinds - flute, oboe, clarinet etc
 * Brass - trumpet, trombone etc.

The Cor Anglais, or French Horn as it is otherwise known, despite the name, is actually a type of oboe so counts as a woodwind instrument.

For more about this see the wikipedia article Musical Instrument

Sometimes composers make ensemble pieces in which only one type of instrument is used, such as a consort of recorders, viols, trombones or whatever.

Or you can combine similar instruments together in an Instrumental ensemble]. The string quartet consists entirely of string instruments - the violin (two of them - the first and second violin), viola, and 'cello. Other ensembles may consist entirely of woodwinds - or brass instruments (think of a brass band), or a combination of both. There the instruments blend nicely together - yet there is something pleasing about the individuality within the blend, for instance the distinctive sound of a viola in a quartet, or a tuba in a brass band.

In other pieces, instruments are used that contrast / complement each other nicely. Some instruments are very companionable as it were, for instance, flute and harp go nicely together.

Generally, it can be nice to combine a plucked or percussive instrument like harp, marimba etc with a melodic instrumnt with a more legato smoothly flowing type of sound such a flute, violin etc. Also it's nice to combine strings with wind instruments - and of course the orchestra has instruments from all the families, often played in episodes in which some of the players take a rest while others play in some contrasting arrangement, or as a little consort of woodwinds suddenly in the midst of it all, or whatever.

The fractal tunes provide an ideal environment for a beginner composer to experiment with orchestration -you don't need to think much about the notes - just focus on the process of intrumentation itself. You may also find you appreciate listening to orchestral music more as a result of experimenting with orchestration yourself in this way.

Instrument ranges
Each instrument has a natural range. For instance, the double bass is a low pitched instrument. You can play it high, but this is rarely done - it has an insteresting rather "thin" kind of a sound when it is played like that. You even get double bass concertos in which the double bass is the solo instrument, mostly played high.

Similarly, flute is usually played high, with middle C as the lowest note - but you can get alto flutes and even bass flutes that go very low. Similarly for other instruments. For instance, the clarinet is usually a high pitched instrument - like the flute though it goes a bit lower. But there are bass clarinets as well, and Stravinsky uses a bass clarinet to great effect in his The Rite of Spring.

Some instruments change completely in timbre depending on the register - the Basson has a very distinctive timbre in its lower registered. When played high however, it sounds almost like a new instrument (this is used to great effect by Stravinsky in the opening of The Rite of Spring).

So that's something to bear in mind. You can either play the instruments close to their natural range - or for effect you can play them higher or lower.

To move individual parts up or down by octaves, go to the Parts window, and highlight the part,and change the Octave Shift (either use the up / down button or type new value in the box below the list).

To find out more about an individual instrument, it's range and other details see the Wikipedia List of musical instruments

Orchestration
So now for our next exercise - to experiment with orchestration. Choose any of the fractal tunes from the drop list. Show the Parts window. This window shows all the instruments used in the tune - the only ones used are the ones up to the number of parts in play.

Vary the instruments in the Parts window
Select one of the instruments, and then change it by selecting a new one from the Instruments menu. Also see what happens when you vary the octave shift. For instance you can try out the Bassoon and see what happens when you play high and low notes.

If you can't quite pick out one of the parts when you listen to your tune, use the Mute button to mute some of the parts. Once you can hear it, put the others back as they were and see if you can still hear it in the complete piece.

Solo instruments
Sometimes one of the instuments in a composition is a "solo" instrument that carries the tune - think of a singer accompanied by harp, lute, guitar or piano for instance. Often the accompanying instruments have their own solo sections when they carry the melody for a while.

With the fractal tunes, generally the fastest tune is the more prominent solo one - but sometimes one of the middle speed ones is. Generally, the one that is at the right speed for the tune to be "singable" is the solo instrument - singable that is in terms of speed at least. Sometimes the tune stays with one instrument, or with fractal tunes, the main tune gets moved around amongst various instruments.

So, think about which instrument one wants to use for the solo line. Usually it tends to be a higher pitched instrument. This isn't by any means an unbreakable rule -think about Dvorak's New World Symphony for instance. Dvorak is an example of a composer who often puts the main melodic line into the bass line. Shubert also often has very singable bass lines even if they are not necessarily the main lines of the piece.

Accompanying instruments
Often the accompanying instruments are lower in pitch - though you often also have many notes which are higher in pitch than the main melodic line - e.g. maybe a piano or guitar will play high notes above the range of the singer they accompany.

You may want to play some of the accompanying instruments more quietly - you can do this using the Volume field.

Which instruments to use for the solo and which for the accompaniment
If you have a combination of a plucked or percussive instrument with a more continuous string / wind / voice instrument, the more continuous one has a tendency to carry the main melodic line more frequently - one could hardly call that a rule as if so, it is frequently broken, but something to think about.

So, experiemnt with various instruments for the main melodic line and try conventional type arrangements where the main melody is continous and high-ish, and also more unconventional ones where it is percussive or plucked or low.

Try various instruments for the accompaniment, and just get a feel of which ones help and which ones obscure the main line.

Pieces with no strong melodic focus
Some pieces too may have more of a chordal than a melodic focus, and may have no strong melodic line at all. Also try making an ensemble type piece where all the parts are played by the same instrument - or select one of the example tunes like that - and try it out with various choices of instrument for the ensemble. You can change the voice for several parts in one go by highlighting them all -click on the first then Shift + click on the last - then select a new voice and you will find it gets selected for them all at once..

Some of the instrumentations chosen for the fractal tunes that come with Fractal Tune Smithy are fairly conventional and some are already unconventional. Have a listen to some of them and see which ones you think sound more conventional and which sound rather unconventional in the instrumentation. Then try your own experiments like that yourself too, either way.

A quick way to build up a fractal tune one voice at a time
Start with File | New . Choose which instrument you want for the first part from the Voices  menu. Now make sure you have Voices | Auto Sel Las  t selected. Increase the Number of Parts to play  one at a time, and each time select a voice from the Voices  menu until you have the number of parts in play as desired - you can do all this while the tune is playing. Then transpose the parts as desired by showing the Parts  window and using the Octave Shift  column as usual. If you want to transpose the entire tune up or down - all the parts at once - use the Pitch  window.

Moving the tune from one instrument to another, and hocketing
Show the Parts window. Then look at the Order of Play menu., and see what you have selected there. If this is a new tune, then you'll find it shows By Layer . You can hear this in the [1.082b/oboe_and_friends.ts oboe and friends] fractal tune. The tune continues normally in the top line, but the start of every seed that begins a new seed at a higher layer gets played by one of the other instruments instead of the oboe. You get this kind of syncopated effect with the oboe often missing the first note of its seeds. So, try that out to hear what it sounds like with your instrumentation.

Many of the fractal tunes use the next selection in this list, By layer with simultaneous notes  Try that instead - you will find the first part plays all its notes, accompanied by the second part playing the same tune,but more slowly - now the extra notes played by the ohter parts get sustained all the way to the next note for that part. And so on - you'll hear a canon by augmentation in fact with your chosen instruments, as explained in [howthe.htm How the seeds build up to make tunes].

Okay, that's pretty nice, many of the tunes use it. However, let's explore the other options here.

'''. By Note height ''' - the same note in the arpeggio always gets played by the same instrument. By time  - the tune just cycles round amongst the instruments, each playing one of the notes in turn. Cummulative note height  is a more complex way of assigning notes to the instruments. Anyway the general idea is that the tune gets broken up by being assigned to each instrument in turn. This is known as hocketting. See the help for this window for a little about those options: [User_guide2.htm#Order_of_play_menu Order of play menu].

Try those various options - then try the Other  option. This lets you make up your own combinations of the other options. Actually, you don't need to try to keep track of what the formula will do. Just enter some formula using the various letters such as t+m+h  or <font color="#0080FF">N+H+L  or whatever, and see what happens. You can try it out with any of the pieces. There are various other options in this window to explore - see it's help [User_guide2.htm#Order_of_Play_Other Order of play | Other]. The option to <font color="#FF8000">Sustain all notes to next note for same part  can be used to get several parts playing together.

Also at this point one could also digress to explore <font color="#FF8000">Bs | Seeds Options | Seed pos increment  as well, perhaps with <font color="#FF8000">By layer with simultaneous notes  - see the help for that window for some informatin about what it does - main effect is you get more notes played in the second and third parts, and a somewhat more complex texture to the fractal tune. One could also try the polyrhythm tunes too - many other things too, but I'll leave those for later FAQ entries on this page. Now, let's go on to the tuning of the notes - the really fun part in my (slightly biased probably) opinion.

Tuning
For this exercise, choose any of the fractal tunes, or one you built up from new in the previous exercises, and try changing the scale from the scales drop list.

As a general guide, ones with fewer notes in them are easier to use, and five or seven or there abouts is enough to have an interesting variety of intervals for the melody, and few enough notes so that nearly everything you play will be nice. Try twelve tone scales with the <font color="#0080FF">pentatonic  or <font color="#0080FF">diatonic  modes (in the <font color="#FF8000">Arpeggios  drop list) - and the minor scales. Then have a look at the other modes for the twelve tone scale (by a mode here I mean a selection of notes from the scale), e.g. the 5 note modes, which you get to from the <font color="#FF8000">Arpeggios  drop list for the twelve tone scales..

If you find the tune goes rather high or low, you can set a range for each part using Note Ranges window. To set the range for several parts at once, highlight all the ones you want to change. The scroll bars shift the bounds of the range by semitones, tones, or the scroll bar below the note number shifts it up / down by octaves.

If you would like an introduction to the various twelve tone systems in the <font color="#FF8000">Scales  drop list at this point, have a look through [#histtuning How do I play the historical tunings of the diatonic and twelve tone systems?] which will get you started. Also have a look through the [Scales_and_Fractal_Tunes.htm <font color="#000000">Musical note intervals ] page for some of the background and theory for them. But, you don't need to know all that to have fun with them - it is just for those who find such things of interest, and kind of useful eventually to know in the long run I expect.

You'll see there are many other scales apart from teh twelve tone ones. Try the <font color="#0080FF">Pygmie  and Koto scales, which are very tuneful, also the Slendro and Pelog which are really interesting and unusual (to the Western ear - these are scales typical of those used in Indonesia). Try the Thailand scale too, which is close to seven equal temperament (seven equally spaced notes to an octave). Generally, try the ones with fewer notes first.

Also be sure to have a go with the harmonic series. This is the series of notes you get in the partials (component frequencies of the note) of many "harmonic" timbres such as voice or string, woodwinds - most of the instruments of the orchestra in fact. The result is that the notes of the harmonic series go well together. See [harmonic_series_notes_sound_well_together.htm <font color="#400040">Why two notes of the harmonic series sound well together ]

For a really unorthodox one try the <font color="#0080FF">Bohlen-Pierce  one - that one should have 3/1 (octave plus a fifth) instead of 2/1 (octave) as the "octave". So in the <font color="#FF8000">Parts  window, change the drop list to read <font color="#0080FF">Modulate by (interval)  and to transpose instruments up / down, use <font color="#0080FF">3  or <font color="#0080FF">1/3  or <font color="#0080FF">9  or <font color="#0080FF">1/9  if you want them to go up and down by two "octaves".

For some more small scales to try go to <font color="#0080FF">Scales | More Scales  drop lists - then the <font color="#0080FF">Woodstock windchimes scale  there is really nice, and also the selection of pentatonic scales labelled " <font color="#0080FF">Canright's exs from Superparticular Pentatonics  ", and " <font color="#0080FF">Canright's Some pentatonics I have known  ".

If you want to be a bit more unorthodox, take some normal type of pentatonic scale like the woodstock windchimes <font color="#0080FF">5/4 4/3 3/2 5/3 2/1 , then change one of the intervals to an exotic one like 11/8, 11/9, 13/8, or some other one using the eleventh or thirteenth or higher prime harmonics. Maybe in this case leave the 3/2 as a kind of grounding thing, so how about <font color="#0080FF">5/4 11/9 3/2 13/8 2/1  or something. Just to get an idea of what those types of intervals sound like in a scale - and if you like it, as usual, save the result for future reference. Sometimes adding just one exotic interval to an otherwise fairly conventional one can be quite striking, as in the [1.082a/bitter_sweet.ts bitter sweet ]fractal tune. That one consists of a normal major chord, with an 11/8 added to it to make the scale <font color="#0080FF">5/4 11/8 3/2 2 . Sounds rather more exotic than you'd expect from adding just one note to a major chord :-).

Another fun thing you can do is to make a scale that is non ascending, or an arpeggio that is non ascending. For instance the piece [1.082a/major_chords_round_the_cycle_of_fifths_-_Bach_temperament.ts major chords round the cycle of fifths - Bach temperament] uses a conventional well tempered twelve tone scale from Bach's time - and then an arpeggio 0 4 7 12 7 which goes up a major chord, and then down to the fifth. As you go up this arpeggio, rather than ending at the octave at each repeat of it, you end a fifth higher instead. So the further you go up it, the further you go round the circle of fifths - hence the title. So the tune gradually wanders up the circle of fifths - but because of the fractal nature of the tune, keeps returning to the home key, at longer and longer intervals of time.

Now that you have an eye for what to look out for, take a look at the scales and arpeggios used for some of the other fractal tunes and they may give you a few ideas.

Then, try out the SCALA scales - you need to install the SCALA archive first - see [FTS_and_SCALA.htm <font color="#400040">Setting FTS up for SCALA and vice versa ] <font color="#400040">. You can order the SCALA scales drop list so that the smaller scales go first in the list, and in fact that's the standard setting for FTS. That's because then the earlier ones in the list will generally be easier to use in the fractal tunes.

<font color="#400040">FTS also has a number of options to help you make your own scales. Take a look at [#New_scales <font color="#0000FF"> Make new Scale ] <font color="#400040">, and the [More_scales.htm <font color="#000000">Scales ] <font color="#400040">help page to find out more about this. Of course, SCALA is an entire program completely devoted to the construction and exploration of new scales.