Session #5, History: Serialism, Loops, Tiling, and Phasing

Chapter 5. Meeting 5, History: Serialism, Loops, Tiling, and Phasing 5.1. Announcements • Musical Design Report 1 due Tuesday, 23 February • Review readings from last class 5.2. Trigonometric Functions and Break-Point Graphs as ParameterObjects • WaveSine: A scalable sine oscillator controlled by seconds or events per cycle pi{}ti{} :: tpmap 100 ws,e,20,0,0,10 waveSine, event, (constant, 20), 0, (constant, 0), (constant, 10) TPmap display complete. • BreakPointLinear: Break point segments defined by seconds or events pi{}ti{} :: tpmap 100 bpl,e,l,((0,.5),(8,0),(16,1),(24,.75),(32,.9),(40,.5)) breakPointLinear, event, loop, ((0,0.5),(8,0),(16,1),(24,0.75),(32,0.9),(40,0.5)) TPmap display complete. • Numerous alternative trigonometric function generators exist as ParameterObjects: WaveCosine, WavePulse, WaveSawDown, WaveSine, WaveTriangle • Numerous alternative break-point function generators exist as ParameterObjects: BreakPointFlat, BreakPointHalfCosine, BreakPointLinear, BreakPointPower 5.3. Configuring Tempo • The TIe command can be use to edit tempo by specifying “b” for BPM • Tempo can be controlled by any ParameterObject 5.4. Approaches to Composing Time • Creating overlapping repeats of the same material • Creating overlapping repeats of transformed material • Creating ordered material that is then transformed in ways that retain order 5.5. Canons and Tiling • Create an initial line and repeat it with staggered entrances • An approach to polyphony • The initial line can be temporally shifted and temporally transformed • Can be seen as an approach to musical tiling 5.6. Listening: Andriessen • Louis Andriessen (1939-) • Dutch composer notable for combining American Minimalism with (at times) more diverse harmonic language • Andriessen: “Hout” (1991) 5.7. Building a Basic Beat • Kick, snare, and hats • Command sequence: • emo mp • tin a 36 • tie r pt,(c,2),(bg,oc,(7,5,2,1,1)),(c,1) • tin b 37 • tie r pt,(c,2),(bg,oc,(3,5)),(bg,oc,(0,1)) • tin c 42 • tie r pt,(c,2),(c,1),(bg,oc,(0,1)) • eln; elh 5.8. A Basic Beat with More Complex Snare Part • Continued command sequence: • tio b • tie r pt,(c,4),(bg,rp,(3,3,5,4,1)),(bg,oc,(0,1,1)) • eln; elh 5.9. Adding Canonic Snare Imitation: Texture Copying • Copying a texture creates a new, independent, and dynamic part • While having identically configured ParameterObjects, if randomness is employed, unique structures will be created • Continued command sequence: • tio b • ticp b b1 • tie t .25, 20.25 • tie i 76 • ticp b b2 • tie t .5, 20.5 • tie i 77 • eln; elh 5.10. Saving and Loading the AthenaObject • An athenaCL XML file can be loaded in to athenaCL to restore Textures • These XML files can be automatically created whenever an event list is created • Continued command sequence: • eoo xao • eln 5.11. Building an Extended Rhythmic Line with Canonic Imitation • Using different length ordered cyclic generators will create complex but non-random sequences • Command sequence: • aorm confirm • emo mp • tin a 77 • tie r pt,(c,1),(c,1),(c,1) • tin b 67 • tie r pt,(bg,oc,(2,4,1)),(bg,oc,(3,5,1,7,1,3)),(c,1) • ticp b b1 • tie t 0.125,20.125 • tie i 60 • ticp b b2 • tie t 0.25,20.25 • tie i 68 • eln; elh 5.12. Creating Mensural Canons • Mensural canons use ratio-base time signatures for each part • Continued command sequence: • tio b1 • tie b c,90 • tio b2 • tie b c,180 • eln; elh 5.13. Extensions • We can generate complex, deterministic patterns by combining cycles at high ratios • The same musical rhythm at different (low ratio related) rates produces interesting musical results 5.14. Tonal, Atonal, and Post-Tonal • • • Tonal music employs functional harmony • Harmonies (chords) have a trajectory, expectation, and a resolution • One (or two) chords are more than others Atonal music does not employ functional harmony • The expectations and priorities of chords are removed • Ideally, no pitch is more important than any other Post-tonal refers approaches to harmony other than tonal • May be atonal, or may employ other approaches to pitch • Pitch centers may be developed and exploited 5.15. Serialism • An approach to atonality that serialized (ordered) elements of musical parameters, developed by Arnold Schoenberg • An alternative approach to atonality employed chords that completed the aggregate (all 12 pitches), developed by Josef Matthias Haur • By serializing the order of all 12-tone pitches, all get equal usage • Pitch groups smaller than 12 can be used • A series of all 12 tones is used as a motivic origin • The series can be transposed to any of 12 pitch levels: prime • The series can be reversed: retrograde • The series can be inverted ((12-n) % 12): inversion • The inverted series can be reversed: retrograde inversion • The 12 x 4 possible rows can be presented in a matrix Generated with Python tools in music21: http://code.google.com/p/music21/ from music21 import serial p = [8,1,7,9,0,2,3,5,4,11,6,10] print serial.rowToMatrix(p) 0 5 11 1 4 6 7 9 8 3 10 2 7 0 6 8 11 1 2 4 3 10 5 9 1 6 0 2 5 7 8 10 9 4 11 3 11 4 10 0 3 5 6 8 7 2 9 1 8 1 7 9 0 2 3 5 4 11 6 10 6 11 5 7 10 0 1 3 2 9 4 8 5 10 4 6 9 11 0 2 1 8 3 7 3 8 2 4 7 9 10 0 11 6 1 5 4 9 3 5 8 10 11 1 0 7 2 6 9 2 8 10 1 3 4 6 5 0 7 11 2 7 1 3 6 8 9 11 10 5 0 4 10 3 9 11 2 4 5 7 6 1 8 0 • Milton Babbitt and Pierre Boulez extended serial techniques to new parameters and alternative organizations • Karlheinz Stockhausen and others attempted to employ serial techniques to organize parameters in the early Electronic Music studio • Total serialism orders amplitudes, rhythms, and other musical parameters 5.16. Listening: Boulez • Pierre Boulez (1925-) • Post WWII and total serialism • Boulez: “Structures, Book I” (1952) 5.17. Extensions • The algorithmic opportunities of serialism led many composers to generalize such techniques with the computer • athenaCL features Paths as a way for Textures to share source Pitch data • One Path might be shared by multiple Textures, each transposing, reversing, and inverting this Path to create serial arrangements • While some have tried (Babbitt 1958), serial rhythm techniques have not been widely embraced 5.18. Phasing • Musical material shifting in and out of time, or moving at different rates • Developed out of manipulations to recording reels: flanging and phasing • Can be used as a canon-like technique 5.19. Listening: Reich • Steve Reich (1936-) • Influenced by techniques of minimalism based in part on music of Terry Riley, La Monte Young, and others • Reich: “It’s gonna rain” (1965) • “Scorification” of a technological process for acoustic instruments • Reich: “Piano Phase” (1967) 5.20. Phasing with athenaCL Python Libraries • pianoPhase.py import os from athenaCL.libATH import midiTools from athenaCL.libATH import osTools from athenaCL.libATH import pitchTools from athenaCL.libATH import rhythm from athenaCL.libATH.libOrc import generalMidi from athenaCL.libATH.libPmtr import parameter OUTDIR = '/Volumes/xdisc/_scratch' BEATDUR = rhythm.bpmToBeatTime(225) # provide bpm value def getInstName(nameMatch): for name, pgm in generalMidi.gmProgramNames.items(): if name.lower().startswith(nameMatch.lower()): return pgm # an integer return None def getSource(repeat): """get source melody and rhythm""" pitchSequence = ['E4','F#4','B4','C#5','D5','F#4', 'E4','C#5','B4','F#4','D5','C#5'] rhythmSequence = [.5, .5, .5, .5, .5] ampGen = parameter.factory(['ws','e',14,0,90,120]) # sine osc b/n 90 and 120 score = [] tStart = 0.0 for i in range(len(pitchSequence) * repeat): ps = pitchTools.psNameToPs(pitchSequence[i%len(pitchSequence)]) pitch = pitchTools.psToMidi(ps) dur = BEATDUR * rhythmSequence[i%len(rhythmSequence)] amp = int(round(ampGen(0))) pan = 30 event = [tStart, dur, amp, pitch, pan] score.append(event) tStart = tStart + dur return score, len(pitchSequence) def transformSource(score, srcLength): """transform source, srcLength is size of each melodic unit """ post = [] octaveShift = -1 panShift = 60 shiftUnit = BEATDUR / 16. eCount = 0 repCount = 0 # starting at zero means first cycle will be in phase for event in score: if eCount % srcLength == 0: shift = shiftUnit * repCount repCount = repCount + 1 # increment after using newEvent = [event[0]+shift, event[1], event[2], event[3]+(octaveShift*12), (event[4]+panShift)%128] post.append(newEvent) eCount = eCount + 1 # increment for each event return post def main(): repeat = 33 partA, seqLen = getSource(repeat) partB = transformSource(partA, seqLen) trackList = [('part-a', getInstName('piano'), None, partA), ('part-b', getInstName('piano'), None, partB),] path = os.path.join(OUTDIR, 'test.midi') mObj = midiTools.MidiScore(trackList) mObj.write(path) osTools.openMedia(path) if __name__ == '__main__': main() 5.21. Beats with athenaCL Python Libraries • basicBeat.py import os, random from athenaCL.libATH import midiTools from athenaCL.libATH import osTools from athenaCL.libATH import pitchTools from athenaCL.libATH import rhythm from athenaCL.libATH.libOrc import generalMidi from athenaCL.libATH.libPmtr import parameter OUTDIR = '/Volumes/xdisc/_scratch' # provide output directory BEATDUR = rhythm.bpmToBeatTime(160) # provide bpm value def getInstPitch(nameMatch): for name, pgm in generalMidi.gmPercussionNames.items(): if name.lower().startswith(nameMatch.lower()): return pgm # an integer raise NameError('bad pitch name') def getKickSnare(repeat): rhythmA = [1, 1.5, .5, 1] rhythmB = [1.5, .5, 1.5, .5] rhythmC = [1.75, .25, 1.5, .125, .125, .125, .125] instA = ['acousticBassDrum','sideStick'] instB = ['sideStick'] ampGen = parameter.factory(['rb',.2,.2,110,127]) score = [] tStart = 0.0 for q in range(repeat): if q % 3 == 0: rhythmSequence = rhythmB instSequence = instA elif q % 11 == 10: rhythmSequence = rhythmC instSequence = instB random.shuffle(rhythmSequence) else: rhythmSequence = rhythmA instSequence = instA for i in range(len(rhythmSequence)): inst = instSequence[i % len(instSequence)] pitch = getInstPitch(inst) dur = BEATDUR * rhythmSequence[i % len(rhythmSequence)] amp = int(round(ampGen(0))) pan = 63 event = [tStart, dur, amp, pitch, pan] score.append(event) tStart = tStart + dur return score, len(rhythmSequence) def getHats(repeat): rhythmSequence = [.5, .5, .25, .25, .5, .5, .5, .5] instSequence = ['closedHiHat','closedHiHat', 'closedHiHat','closedHiHat', 'closedHiHat','openHiHat'] ampGen = parameter.factory(['rb',.2,.2,50,80]) score = [] tStart = 0.0 for q in range(repeat): for i in range(len(rhythmSequence)): inst = instSequence[i % len(instSequence)] pitch = getInstPitch(inst) dur = BEATDUR * rhythmSequence[i % len(rhythmSequence)] amp = int(round(ampGen(0))) pan = 63 event = [tStart, dur, amp, pitch, pan] score.append(event) tStart = tStart + dur return score, len(rhythmSequence) def main(): repeat = 33 partA, seqLen = getKickSnare(repeat) partB, seqLen = getHats(repeat) trackList = [('part-a', 0, 10, partA), ('part-b', 0, 10, partB),] path = os.path.join(OUTDIR, 'test.midi') mObj = midiTools.MidiScore(trackList) mObj.write(path) # writes in cwd osTools.openMedia(path) if __name__ == '__main__': main() 5.22. Building an Extended Rhythmic Line with Fixed Tempo Phasing • Using different tempi will create shifting rhythmic patterns • Command sequence: • aorm confirm • emo mp • tin a 70 • tie r pt,(bg,oc,(2,4,4)),(bg,oc,(4,1,1,2,1)),(c,1) • tie t 0,60 • ticp a a1 • tie b c,124 • ticp a a2 • tie b c,128 • eln; elh 5.23. Building an Extended Rhythmic Line with Dynamic Tempo Phasing • Oscillating the tempo at different rates will create dynamic changes • Command sequence: • aorm confirm • emo mp • tin a 64 • tie r pt,(bg,oc,(2,4,4)),(bg,oc,(4,1,1,2,1)),(c,1) • tie t 0,60 • ticp a a1 • tie i 60 • tie b ws,t,20,0,115,125 • ticp a a2 • tie i 69 • tie b ws,t,30,0,100,140 • eln; elh 5.24. Extensions • Many works have been built with slow and gradual tempo changes • Tempos might slowly deviate with a BreakPointLinear or similar generator • Tempos might be randomly perturbed by adding in randomness: PO OperatorAdd can sum two ParameterObjects pi{}ti{} :: tpmap 100 oa,(ws,e,20,0,0,10),(ru,-2,2) operatorAdd, (waveSine, event, (constant, 20), 0, (constant, 0), (constant, 10)), (randomUniform, (constant, -2), (constant, 2)) TPmap display complete.