HITHER GATE MUSIC


Sonic Transitions

~ A 4-Stage Sound Design Illustration ~

prepared by A Endrich

from a passage in Crossing the Dark Rift

Goal: a single whoosh which glisses downwards from soft, fuzzy attacks,
through a a chord, and into a texture of bell-like sparkles

Stage 1: prepare a comet shower

Source: single stroke on a Tibetan singing bowl: bdtg5.wav (4.9 sec), DOVETAILED to give a smooth start and finish.

A 4-note chord is made from this sound by SPECTRAL TRANSPOSITION (durations remain the same):
bdtG5DGBCsh.mp3. This chord is transformed with ENVEL PLUCK: wavelength for the pluck is 1000 (not too long), the attack cycle is 100 (not too many, but enough), and the decay rate is 2 (slow). The 1st 2 seconds of the result are CUT and DOVETAILED to form 2 seconds of fading noise: noisefade2secdt.mp3, rather a surprise result, given the input.

This fading noise, comet-like sound is used as the input for TEXTURE SIMPLE, Mode 5, giving an output duration of 12 seconds. The aim is to create a group, a shower of comets whizzing by. Reference pitch is MPV 60 (Middle C).

PARAMETER	TIME_START	TIME-END
		0.0		12.0
		VALUE_START	VALUE_END
Event-Density	0.7		1.5
Pitch-Hi	72		60
Pitch-Lo	48		60
Loudness-Hi	84		15
Loudness-Lo	64		 5
Result: 12 seconds of fuzzy noise iterations, spread at first and then coming closer together (slowing down and getting quieter) until note events repeat near the reference pitch, the untransposed original sound. cometshower.mp3


Stage 2: create glissandoing chords

Source: the same bell-like tone from a Tibetan singing bowl that we used to create the comet sound: bdtg5.wav (4.9 sec.)

The first step here is to create two large chords by SPECTRAL TRANSPOSITION (durations remains the same) and MIXing all the transpositions for each chord: tz5upchorddt.mp3 and tz5dwnchorddt.mp3. These chords are dovetailed, 0.3 at the start and 1.4 at the end – a long fade to help them blend in with the bell-like clusters to follow, and then time-stretched times 1.5 to make them a little longer.

The first of these chords is transposed down a minor third and the second down a major second, forming:

Now the A, Bd2 and Ad3 versions are transposed over time so that they will gliss downwards through a minor third. This gives us three downward glissandoing chords, each of which starts a little lower than the one before:


They are: tz5upchorddtstrtvd3.mp3, tz5dwnchorddtstrd2tvd3.mp3, tz5upchorddtstrd3tvd3.mp3

Notice how all of the above steps are stated in the soundfile names: 'chord' for forming a chord, 'dt' for dovetail, 'str' for time-stretch, 'd2' and 'd3' for the two chords which are transposed down 2 and 3 semitones respectively, and 'tvd3' for a time-varying (glissando) transposition through a minor third.


Stage 3: create a cluster of bell-like sparkles

Source: dovetailed Tibetan bowl tone: baegcdt.wav. Note that this version has a much sharper attack. This is to keep a sparkle in the clusters we will be making – bdtg5.wav actually came from this sound, softened with DOVETAILING to make the attack transient more gradual, softer.

First we lighten the tone with a HI-PASS FILTER, i.e., let through the upper frequencies and cut out the lower ones. The cut-off frequency is 1568 Hz, with the filter's slope ending at 10 Hz. Thus we have a gradual frequency roll-off down to the bottom of the sound: not too sharp. This creates baegcdthipc.mp3 (4.8 sec.).

This forms the input for TEXTURE SIMPLE, Mode 5, given an output duration of 4.8 sec. (same as input sound) – it actually comes out longer as the various interations of the input play out their full length as specified by the 'whole input' option. The result is given a harmonic colour related to the first chord by snapping all the cluster note events to the following harmonic set:
The cluster texture is shaped with an increase in density and amplitude towards the centre, then slowing again. The amplitude peaks off-centre, at time 3.0 sec.

TIMES		0.0	1.0	2.0	3.0	4.0
Event-density	0.1	0.04	0.01	0.08	.25
Loudness-Hi	10			84	44
Loudness-Lo	10			64	34

Result:clustertz1s8g.mp3. A little gain was applied to top up the overall amplitude. Again, we need to continue to glissandoing, so this soundfile now undergoes the same transpositions as the chord:

  1. time-varying down a minor third: clustertz1s8gtvd3.mp3
  2. with a second version first transposed down a major second: clustertz1s8gd2tvd3.mp3
  3. and a third version transposed down a minor third: clustertz1s8gd3tvd3.mp3


Stage 4: MIX everything together

We get the final result by putting the results of the previous processing together in a MIX operation. The timing of each entry is arranged to have all the components fuse together into a single evolving sound: a sonic transition. Note that everything has come from the same sound (baegcdt.wav).

tz5s8mx.mix (times only)

TIME

SOUNDFILE

ROLE

0 cometshower.mp3 a burst of comet activity
5 tz5upchorddtstrtvd3.mp3 1st chord glissando, starts at original pitch
8 tz5dwnchorddtstrd2tvd3.mp3 2nd chord glissando, starts a major second lower
9 clustertz1s8g.mp3 1st cluster, to form a tail for the 1st chord
11 tz5upchorddtstrd3tvd3.mp3 3rd chord glissando, starts a minor third lower
12 clustertz1s8gd2tvd3.mp3 2nd cluster, to form a tail for the 2nd chord
15 clustertz1s8gd3tvd3.mp3 3rd cluster, to form a tail for the 3rd chord

Result of Mix: comets with long descending tails filled with harmonies and dispersing in clusters of incandescent sparkles tz5s8mix.mp3. This composite sound is used for the 8th month of the 5th 'Tzolkin' year in my composition.


Last updated: 2 November 2010
mp3 format changes: 21 February 2010 (sources or near sources are kept as wav)

©2003-2010 Archer Endrich Chippenham, Wiltshire  England, both texts and music. All rights reserved.