Downloads
The Opus+ software is still under development, so currently we cannot offer the actual software. However, for those who are interested we will give some indication of how the research is progressing by periodically publishing the musical test sequences generated by the neophyte code. Links to these are shown below along with the date the test was run. Most of these sequences are 'found as is'; they have not been edited or altered by human hand in any way, and where they have these human edits are described in full.
'Summer in Algiers' named after the book by Albert Camus, was also part of the 'experiment with order', and starts with a beautiful haunting section which relies on an interplay between the instruments that is very hard to conceive of being written by a human. It then progresses to a lovely open, free sequence that continues to the end (which might have been better finished with a gentle fade out!). Although this music is complex on the printed page, we believe that musicians with sufficient wherewithal would be able to play this reading from score, having been given enough practice time prior to performance.
This was the forth piece mixed through Apple Logic and, as a comparison with the original MIDI file shows, the orchestration in terms of the voicing’s and instruments really affects how parts of the composition are elevated. This can be heard in bar 14 where the first guitar appears to introduce a new phrase and starts to play completely across the established rhythms. In the original MIDI the effect is quite jarring, whereas in the mixed MP3 it sounds completely natural, adding space and depth.
27th January 2008: [Score as PDF] [Music as MP3] [MIDI File]
'From the Planet Gong' was also generated in the series of tests looking at creating music with a more ordered form using a software entity called a state-machine. As the music is written for each instrument a state-machine is used to control how repetition and variation within the piece are balanced. The result is a composition in a set of six 24 bar sections, and in all cases, the drums, bass, backing guitar and marimba all play a regular repeating pattern of some description. In the first 12 bars of each section, the lead guitar is silent to give the listener a chance to become acquainted with the pattern, and then in the next half the lead guitar is allowed free reign.
The production quality is comparatively superb as a result of going through the Apple Logic software, and we lost count of the number of Steve Hillage air-guitar impressions we had during mix-down!
27th January 2008: [Score as PDF] [Music as MP3] [MIDI File]
'Prelude for Piano' was created during some tests looking at the sorts of rules necessary to generate interesting piano parts. Piano compositions are notoriously difficult to write convincingly, so we examined the scores of some Bach preludes in an attempt to understand something of the musical structure, so this might guide our choice of parameters. This was an incredibly interesting exercise, and after a few runs, this piece occurred. It's not Bach, but it does have a musical theme which develops, a tune is discernable, and the piece moves and resolves in a natural sounding way. The two chords at the end were the result of a very short section consisting of a single bar where the constraints were set such that chords were certain to occur. From the pianist's perspective its level of difficulty is probably about grade 8.
This test also revealed a requirement that we improve the way Opus+ handles piano score layout. The issue has to do with piano staves, which unlike other instruments, have two voices that can move between the treble and bass staff. In any bar, the voices can swap between treble and bass, or they can both play down in the bass or simultaneously up in the treble. This means that it is possible to get 'crossed beams' (i.e. bars 2 and 11 for examples) which look untidy and are difficult to read. Work is in progress to rectify these issues as far as possible.
27th January 2008: [Score as PDF] [Music as MP3] [Velocity Re-mix MP3] [MIDI File]
'Tessellation Chromatix' occurred one evening during a new set of experiments using Opus+ with constraints which produce much more 'ordered' or 'regular' compositions. The idea tested here is that music is essentially about repetition at its most fundamental level. Any musical phrase repeated a few times, assuming that the phrase is short enough to be retained in the listener's memory, is heard as musical. In this piece each instrument has its own cyclic phrase. The bass repeats the same 1 bar phrase continuously, while the marimba and drums lay down a 4 bar back-beat. The guitar uses a phrase 3 bars in length which means that all the instruments only coincide every 12 bars. After the first twelve bars the Sax comes in over the top with an 'improvised' solo, which has no constraints to enforce repeating phrases.
We noticed that if the Sax was allowed to start immediately from the first bar, it was very difficult to hear the musical nature of the repeating 12 bar cycle because of its complexity. By having the Sax only come in after the twelfth bar the musical cycle can become established in the listeners mind and the music is heard entirely differently - as a back-beat with a Sax solo over the top - rather than a complex jumble of notes.
This was also the first piece we imported into Apple Logic to produce a roughly mixed MP3. We probably didn't choose the right instrument voice for the Sax, but the end results were so much better than we had heard before from Opus+, some of us were literally dancing around the studio!
27th January 2008: [Score as PDF] [Music as MP3] [MIDI File]
Bars 43 to 80 of 'The Band Practice' was 'composed' while I was in Geneva waiting for a pizzeria to open. I used Opus+ to generate the music, changed the original trumpet part to that of guitar to more naturally accommodate the chords that had been created, (I had the constraints set incorrectly) and dropped the original bass line by one octave (again because I had the octavation constraint incorrectly specified). Then a few days later another piece appeared during a program test run with a very similar 'feel', and the phrase in bar 15 offered a really easy way to link these pieces together. The end result reminds me of a latin band warming up in a practice studio and at about bar 23 they suddenly get 'in the zone' ...
3rd and 12th December 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Synth Pop' produced by Opus+ completely artificially, is twenty bars in duration and quite simply sounds brilliant! It's a complete surprise to me just how convincing this sounds, (from a compositional perspective, not performance or production), so I took the liberty of copying and repeating the twenty bars three times to make a 2 minute pop/dance track. Now where's my agent.... ;-)
15th November 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Maximum Funk' is artificially generated! One has to keep this in mind listening to it. There is actual 'structure' here. A slow intro with marimba and guitar that builds, gradually introducing the other instruments and building the listeners expectation, leading to the drums which come in at the start of bar thirteen with a cymbal crash and then they stay under-pinning the whole piece as it builds to a climax. It then changes to 5/4, rather too abruptly, and continues in a hard funk style to the end - which is also somewhat 'interrupted'.
15th November 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Strange Beeps That My Ears Hear' is another short piece which vaguely reminds one of the backing for a Captain Beefheart track in the style of 'The Thousand and Tenth Day of the Human Totem Pole' on the most excellent album 'Ice Cream for Crow'. Not of course in the instrumentation or in recording quality - it's not even close - but in the way that it stumbles and jerks clumsily as a musical piece. Even if you disagree with this comparison, as a composition it sounds purposeful as if it was written by a human composer, albeit not a very good one!
13th November 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Harmony' is a short piece of 10 bars duration in 5/4 generated as part of a test suite where fragments of music are transformed and located on the staves according to a complex compositional constraints. It has a lovely rolling rhythm and a definite sense of tuneful progression. This is probably the first music that Opus+ produced that sound like part of a human composition as a block. In fact it is reminiscent of some hard underground funk from the 1980's.
9th November 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Minimum Funky' was the result of a test run on a set of compositional constraints which locate multiple fragments of music across a set of staves and through time - a sort of interleaved continuo. These fragments themselves were generated entirely at random and are included here mainly because of the guitar part; it is the epitome of 70's funk at it's very best.
9th November 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Jazz Trio' is an entirely unconstrained linear run which in many ways is a 'step backwards' in terms of the way that Opus+ operates, but is included here because it was the first actual music generated after some ten months of work re-factoring the code and radically simplifying the design of the Opus+ library internals to make the entire code base easier to understand and use. Six months of was 'wasted' experimenting with Java template code, which proved to be unsuitable for Opus+ in this context. So this generation of Jazz Trio was a sure sign that we could get back to creative coding, and with the hope that this would proceed more rapidly here on in.
19th October 2007: [Score as PDF] [Music as MP3] [MIDI File]
'Christmas Collage' works with fragments of well known hymns and their inversions, combining them using pseudo-random mathematics. This is probably the most musical piece so far produced by Opus+, and its an interesting exercise to try and recognize which hymns have been used. Happy Christmas from everyone at Opus+!!!
12th December 2006: [Score as PDF] [Music as MP3] [MIDI File]
'Celebration in G# min' uses musical fragment combination techniques described below, but tests that they work with drum staves, and there are also weights applied to fragment selection algorithms, fragment transforms and stave selection. This test also uses a musical phrase fitting algorithm which requires that notes be tied across bar lines. The result is undeniably musical, if somewhat pedestrian.
6th November 2006: [Score as PDF] [Music as MP3] [MIDI File]
'From Here to Ju-Ju' is another piece generated from random musical fragments, transformed and combined in unusual ways, but this time there is a distinctive emergent Ju-Ju musical flavour, with alternating bass and answering phrases. Admittedly this style never really establishes itself as it continually collapses into a more chaotic and discordant bastardization thereof, but this is interesting in itself because it's hard to conceive of anyone actually writing something like this.
11th October 2006: [Score as PDF] [Music as MP3] [MIDI File]
'Forget Shakti' is one of the first pieces generated using a technique which combines random fragments of music, each of which can be transformed in a finite number of ways. Purely by coincidence the result was a distant reminder of the work by the superb and utterly peerless band Shakti - hence the name - a play on a recent album entitled 'Remember Shakti'.
10th October 2006: [Score as PDF] [Music as MP3] [MIDI File]
The main purpose of this 'Rock n'Roll' experiment was to test how different weightings could influence different parts of the composition independently. For example, here the weightings used for the drums greatly simplify the drum parts produced when compared to unrestrained 'jazz' style compositions, yet the guitar part creation is constrained by a different set of weights, which is biased towards small, quick notes creating a contrasting musical effect.
20th June 2006: [Score as PDF] [Music as MP3] [MIDI File] [Re-mix as MP3]
This piece is called 'Rest' because it arose from a test for a routine that analyses musical rest layout. The mathematics underpinning all decisions made during 'composition' are based on a series of integers produced using fractal mathematics; the same sequence that inspired the Mandelbrot set. There are several interesting aspects to this piece. Firstly, it sounds musical. There is a strong sense of a minor key throughout. Secondly, there is an 'invisible pulse' that is subtly apparent through the entire piece. This is stronger in some sections than in others. This is interesting because in nearly all music, the pulse is explicitly stated, whereas here it is implied by an 'emergent conspiracy between the individual instruments'. Thirdly, repeating themes appear with slight variations, which is perhaps unsurprising considering the use of fractals, but at some points the instruments really sound as if they are responding to each other, particularly where some instruments pause for a few bars and the music seems to almost stop only to continue in a quite unexpected way. Fourthly, the piece would be fiendishly complex to perform, and as such is unlikely to be composed by a human, although it could conceivably occur as an improvisation. Lastly, it actually sounds restful. This subjective experience is invoked by the performance of artificially composed music.
1st May 2006: [Score as PDF] [Music as MP3] [MIDI File]
This piece, called 'Jazz Invention III' (ooo-er missus!), was generated during a test on 'tonal centres'. Every four bars it cycles between the scales of A minor, C major and the chromatic scale. All decisions regarding pitch, duration and other musical features were taken based on the mathematics of the Fibonacci series, and because the lower bits of the numbers in this series repeat every sixty terms or so, repetitive patterns emerge.
6th November 2005: [Score as PDF] [Music as MP3] [MIDI File] [Re-mix as MP3]
Scales is the first ever 'sound' generated by Opus+, where it proves it can generate all the standard musical scales accurately. Checking that your scales are perfect is just as important for programs as it is for musicians, because we want to ensure that all composition algorithms are translated faithfully to the correct pitches.
17th July 2005: [Score as PDF] [Music as MP3]