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Amplitude and Loudness 1◆ intensity of vibration ◆ measured in dB-SPL (sound pressure

level) ◆ range for humans 0 (threshold of hearing)

to 120 (pain) and beyond

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LOUDNESS CHART● 0--threshold 1 ● 20 quiet living room 10 ● 40 subdued conversation 100 ● 50 average office 316 ● 60 average conversation 1000 ● 70 busy street 3162 ● 80 acoustic guitar 1' away 10000 ● 90 heavy truck 31620 ● 100 subway 100,000 ● 110 power tools 316,200 ● 120 threshold of pain 1,000,000 ● 130 rock band ● 150 permanent hearing damage ● 180 rocket engine

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Amplitude and Loudness 2◆ dBm

● levels of electrical power (in milliwatts) ● signal strength ● Right side is in decibels ● 0 dB is maximum w/out distortion ● left side is % of maximum modulation ● if signal too low--noise introduced ● signal too high--distortion ● Can have very high dB-SPL and still good levels-- ● must monitor

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Inverse Square Law of Sound◆ Sound intensity varies inversely with the square of the

distance between the sound source and the microphone

◆ I = 1/r squared (r= distance) ◆ Double the distance ● 1/4 the intensity

◆ Halve the distance ● 4x the intensity

◆ Get the mic as close as possible ◆ Moving a mic a little makes a lot of difference

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Phase◆ time relationship between 2 or more

sound waves at a given point in cycle ◆ in phase, increase amplitude ◆ out of phase, decrease amplitude--

cancellation ◆ microphone and speaker placement ◆ polarity

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Phase diagram

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Phase example-Polarity switched

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Sound Envelope

◆ changes in loudness over time ● attack ● internal dynamics ● decay

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III. WHAT DOES SOUND DO. ● Sound gives us:

◆ Music ◆ Spoken Word ◆ Sound Effects ◆ Silence

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MUSIC

◆ Same structural/technical elements as sound ● pitch, loudness, tempo, tone color, and

envelope ◆ But also has:

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1. melody

◆ succession of pitched musical tones of varied pitches, durations and groupings

◆ rhythm--the groupings of individual notes ❖ 1-2-3, 1-2-3, 1,2-3 ❖ 1-2-3-4, 1-2-3-4, 1-2-3-4 ❖ accent on the first note

◆ pitch -- frequency of individual notes

◆ What we remember most in music

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From ?

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A melody has Key or Tonality◆ keys or tonalities ● major

◆ positive, happy, bright, vigorous ● minor

◆ darker, melancholy, wistful

◆ based on the harmonic structure

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Major Key to Minor Key

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Melody is “characterizable”● simple ● melancholy ● plaintive ● sentimental ● romantic

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Simple Melody◆ Paraguayan Dance--Manuel Barrueco

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Melancholy◆ Rachmaninoff Prelude

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2. Harmony--simultaneous sounding of 2 or more tones

◆ juxtaposition of notes ● simultaneous ● in sequence

◆ consonant--agreeable, settled, balanced, stable

◆ dissonant--unstable, unresolved

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Dissonance joe lulloff and ron Newman

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Dissonant to Consonant

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3. Texture

● created by the interweaving of melody, timbre and harmony ◆ delicate, ◆ coarse◆ dense◆ airy◆ brittle,

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Delicate to Dense Texture

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4.Timbre◆ most sound is not pure ◆ harmonic structure is combination of sounds which

produces timbre. ◆ no objective scale--subjective ◆ created by overtones ◆ We describe with non-technical terms ● metallic, sweet, wood-like, buzzing

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6. Dynamic range◆ crescendo--quiet to loud ◆ diminuendo (decrescendo)--loud to soft ◆ Interpretive tool ● build or release tension

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Dynamics--Mahler: long decrescendo

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