Ecosphere Signal Processing Details

Two macintosh computers running a complex program written in Max/MSP (by Olivier Pasquet) are used to perform digital signal processing on all instruments. Below is a list of cues that occur throughout the piece, with the cue number, measure number, and the signal processing that occurs in that section.

Glossary of Processes:

Resonance: resonant filters are deployed to create an effect similar to the sympathetic resonance that occurs when the pedal of the piano is depressed

Delays: delay lines are deployed to create echos of the original signal

Reverberation: digital simulation of sonic reflections that occur in large rooms with hard surfaces

Harmonizing: the signal is reproduced (with a slight delay) with the same timbre and a different pitch, used to create tri-chords with just tuned intervals from one original note

Chorusing: harmonizing at a very close, fluctuating interval, producing slight beating and enriching the original signal

Cross-synthesis: the timbre of one instrument is analyzed and this data is used to modulate the timbre of another instrument, creating an effect similar to vocoding

High-pass filter: low frequencies are removed from the signal

Spatialization: a number of different kinds of spatialization are deployed throughout the piece: X/Y refers to random movement in straight lines between the speakers and circle refers to random circular motion. At other times specific patterns of movement are synchronized with musical gestures, or instruments are assigned to different static positions.


cue #  mea.#          description


1          1             entire ensemble excites resonance in all speakers

2          5             turn off silent instruments

3          6             vibraslaps into delays and moved to rear speakers string tremolos move around randomly (X/Y)

4          8             adjust levels, crotales and vibraphone delayed in three speakers at different rates

5          17            cancel previous, turn on all instruments with resonance in all  speakers (as in cue 1)

6          20            turn off silent instruments

7          22            assign instruments to different speakers so cross fades pan


8          27            brass excite resonance (shorter decay then cue 1) and reverberation, percussion scrapes into delays in rear speakers

9          33            turn off silent instruments


10         50            all instruments amplified with reverb in front vibraslap delays in rear

11         53            trombone into multiple delay lines, all in  center speaker, then moving out to rear and side speakers (in 5 seconds) where they stay for the whole section.

   Crescendos in other instruments pan quickly and randomly (X/Y) among all the speakers

12         80            trombone continues in delays but quieter, crescendos continue as before, oboe randomly moves among speakers (X/Y) with heavy reverb,
string jete's in delay lines in multiple speakers

13         84            flute into multiple delays, panning randomly (X/Y), viola into delays, but stationary; everything else continues as in 12

14         101          gradually increase level of trombone delays

15         112          turn off silent instruments, turn on string amplification with reverb, trombone continues in delays


16         124          cello with FFT delay (throughout movement), clarinet with 2 voice harmonizing with changing intervals in subsequent cues (start here 351 and -200)

17         125 b.2     clarinet intervals change:200, -200

18         125 b.4.5  clarinet intervals change:640, 351

19         126 b.4     clarinet intervals change:200, -200

20         127 b.5     clarinet intervals change:551, -498

21         128 b.2     clarinet intervals change:200, -200

22         129 b.1.25 clarinet intervals change:651, -700

23         129 b.4     clarinet intervals change:200, -200

24         130 b.3.5  clarinet intervals change:651, -500

25         131 b.1.5  clarinet intervals change:200, -200

26         131 b.4     clarinet intervals change:386, -231

27         132 b.5     clarinet intervals change:200, -200

28         133 b.2     clarinet intervals change:351, -431

29         134 b.2.5  clarinet intervals change:569, -500


30         136          cor anglais with chorusing and reverb in right speakers, viola with chorusing and reverb in left speakers, other strings excite resonance in all speakers


31         147          two voice harmonizing on flute (200, -200) on left, and clarinet (640, 351) on right, other instruments amplified with reverb

32         152          two voice harmonizing on oboe (714, 470) in center, others continue


33         167          solo violin in top center speaker with resonance

34         168          violin moves to rear

35         168 b.5     violin moves to left side, bass clarinet is amplified in center

36         170 b.3.5  violin immediately to top center speaker again, then moves to rear, then left side

37         172 b.3     violin moves around to right side

38         173 b.2.5  violin immediately to top center, then back down to rear 


39         175          w.w. and brass in individual speakers for hocketing, strings with delays in front

40         175 b.3     percussion 1 moves around randomly (circle) with heavy reverb, everything else continues 


41         183          all instruments move randomly (x/y) with delays, chorusing, and resonance

42         201          everything continues, levels adjusted, horns with delay in front speakers

43         230          continues, levels adjusted 


44         247          everything off from previous section, all instruments amplified in front with reverb

45         250          harmonizing on strings fade in: v1 (10), v2 (440), vla (351), vc (269)

46         250 b.5     cross synthesis: when bass plays it is modulates strings in rear speakers, bass clarinet modulates strings in left side, and trombone on right side

47         255          change string intervals: : v1 (740), v2 (651), vla (269), vc (186)      

48         258          change string intervals: : v1 (740), v2 (10), vla (151), vc (-431)

49         261          change string intervals: : v1 (740), v2 (351), vla (-714), vc (-431)

50         263          change string intervals: : v1 (451), v2 (-260), vla (-431), vc (-331)

51         266          delay and chorusing on v1 and 2, harmonizing on vla . (351), and vc (269)

52         268          delay and chorusing on v1,v2,vla, two voice harmonizing on vc (551, -231)

53         270          add delay to cello

54         272          harmonize V1 (569)

55         274          harmonize Vla (386)

56         278          change V1 interval (10)

57         279          change vla interval (10)

58         280          chorusing and delays on v1,2, vla, and vc

59         283          harmonizing on strings fade in: v1 (269), v2 (-200), vla (186), vc (500)

60         284          change intervals: : vc (-231)

61         285          change intervals: : vla (151), vc (269)

62         287          change intervals: : vla (186), vc (551)

63         289          change intervals: : vla (151), vc (-231)

64         293          delay on bass clarinet, bass and trombone

65         295          turn off delay on bass and bass clarinet

66         296          turn on delay on bass, off on others

67         299          loud delays and harmonizing on wind and percussion with fast random movement (x/y) 


68         314          all instruments with delays, moving randomly (x/y), and exciting heavy resonance which gradually fades away over 30 seconds, clarifying the sound

69         380          delays and motion continue (no resonance) high pass filter gradually rises in frequency over 30 seconds, filtering away lower part of spectrum
and leaving shimmering high harmonics moving around


70         393          filter is removed, instruments amplified with reverb in fixed positions around the room

71         395          all instruments move to new position in 2 seconds

72-77    397-419    (with percussion unisons) instruments move to new position, 2 instruments are given delays and x/y random movement (different ones each cue)

78-80    425-435    (with percussion unisons) gradually add instruments to random rotating movement

81         441          slow movement slightly, gradually introduce resonance

82         445          gradually introduce delays on all instruments

83         449          all instruments slowly circle randomly, with resonance and delays (like at the start of Rain Forest)

84         467          ob, vla, horn 1 slightly louder and move randomly in X/Y mode, others stay the same

85         474          cl1,v2,h2 slightly louder and move randomly in X/Y mode

86         480          fl,v1,trb slightly louder and move randomly in X/Y mode

87         483          cl2,vc,bs slightly louder and move randomly in X/Y mode

88         490          vla, vc, v1 in x/y random movement (no delay)

89         493          cl2, bs, trb join x/y movement

90         495          h1,h2,ob,cl1 join x/y movement

91         496          vl and v2 join - all instruments moving randomly (x/y) - gradually introduce resonance with short decay time in all speakers

92         508 b.2     all instruments move to front speakers in 1 second and stay fixed with reverb, resonance fades in 1 second


93         510          all strings with harmonizers that raise and lower the frequency in proportion to the amplitude of the bass clarinet (when is not playing, they have jittery chorusing, as he plays louder one pitch moves down and another up to a whole tone cluster when cl. reaches FF). Bass clarinet also modulates the timbre of the strings (cross synthesis), and pans the strings (front when quiet, rear when loud). Bass clarinet itself is in rear speakers.

94         523          turn on flt, ob, cl1 with reverb in front


95         535          all instruments random movement (x/y) independently

96-99    538-543    movement of instruments becomes identical when they play in unison, until everyone is moved the same at cue 99

100-102 548-546    reverse process, instruments move independently as they depart from unison

103       556          everyone independent again, turn on brass in front speakers with reverb

104       558 b.2     begin processing for next movement: cello delays, clarinet 2 voice harmonizing with shifting intervals (starting with 351, -231)


105       559 b.3     change clarinet intervals (200, -200)

106       560 b.2     change clarinet intervals (351, -698)

107       561          change clarinet intervals (-569, -431), two voice harmonizrer on flute (551, 396)

108       562          change cl. intervals (351, -700), change flt intervals (569, -500),  2voice harm. on oboe (-131, -400)

109       565          change cl. intervals (186, 641), change flt intervals (251, -200)

110       565 b.4     change oboe intervals (269, -800)

111       569 b.1.5  change intervals cl (286, -459), flt (351, -200)


112       573          all instruments excite resonance, string tremolos move around randomly (X/Y), trombone and horns with delays

113       577          add viola to high string movement

114       581          remove viola from movement

115       585          delay on percussion, everything else continues

116       589          turn off silent instruments, increase delays on trombone and horns

117       600          tremolo strings move around together randomly (circle), percussion with heavey delays and reverb in rear speakers

118       609          turn everything off and go someplace to drink a lot of champagne, wine, and cognac!