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You can easily see the waveform of sound in a display. The sound
texture diagram makes use of the X-Y coordinate system but is
based on either the fundamental frequency and incoming audio
signal and time relating to the music tonal system.
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Musical Instrument Features
The shape of the diagram varies very little from low to high frequency.
For example, the flute generates pretty pure tone, and its
wave feature diagram looks like a perfect circle. Violins
and other musical instruments with their own resonance chamber
usually provide much richer tones and their resonance frequencies
result in slightly and sometimes significantly different shapes
over the musical tonality scale. In fact, most musical instruments
have slightly different wave features over the range of pitch
that it can generate music.
Moreover, the sound of most musical instrument varies from one cycle
to the next cycle. The most notable is the church organ.
All the above are reflected in the sound texture diagram as easily
recognizable shapes or shape transition profiles. This diagram
is a good way to analyse the inherent nature of the musical
instrument over its intended usage range. It also helps in
drill exercises in certain musical instruments like the flute,
which will result in imperfections and can be seen easily
on the diagram when it is not played well. It is also a helpful
assistant to the musician to get in touch with the subtleties
of musical composition, as described below.
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Note Mixing Effects
When two notes mix, interesting patterns arise.
Basically, two notes with their frequencies in simple ratio
will result in clear patterns.
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Sound combination
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Wave feature diagram
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Audio result
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Same pitch from two tuned musical instrument
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One clear slowly-varying pattern
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Two sounds merge into one, resulting in a single harmonious sound.
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Two neighboring tones
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Spiral pattern, may flash
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Rapid beating
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Two notes from same instrument which is one octave apart
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One clear stable or slowly-varying pattern
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Two sounds merge into one.
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Two notes from same instrument which is a fifth apart
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One clear stable or slowly-varying pattern
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For many temperament scale, fifth is 3/2 times of the base
frequency. However, the equal temperament scale is slightly
off from the exact 2:3 ratio.
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Two notes of frequencies in simple ratio
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Kaleidoscopic
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Kaleidoscopic
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Pitch Features
In another forum of sound texture diagram, the wave feature
diagram shows both the audio texture and the pitch. The pitch
aspect is reflected as a slanting angle of the diagram. So
a pure tone will appear as an oval of varying slanting angle
depending on the pitch of the note. Other than that, it looks
and behaves like the normal sound texture diagram.
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Technology
