Sound And Light Training
SALT Manual

by Ken Ellis
(last update 2001-05-19 - Ken Ellis)

11. Understanding Sound

  1. The Decibel - dB

  2. Frequency Range of the Human Voice

  3. Recognizing the Frequency of Sounds
  4. It is important for a sound technician to learn to recognize the frequency of sounds so you are able to quickly and correctly adjust equalization when there is a problem (i.e. feedback, hollowness, nasal sound, boomy, etc.)

    When you have time alone with a sound system, put on some good quality music and play with the graphic equalizer to learn what frequency range each control affects. Memorize the tonal quality each control affects.

    40-60 Hz Boomy - a sound over abundant in low lows. These waves move a lot of air, hence Boomy.
    60-150 Hz Fat - the octave above Boominess. Makes things sound big, but not earth- shaking.
    125-250 Hz Woofy - a somewhat nebulous term for sounds that are sort of "covered" - masked by low-end energy.
    250-500 Hz Puffy - is like an octave above Woofy. It's still sort of a cloud, but not as big.
    200-400 Hz Warm - obviously a positive characteristic often found between 200 and 400 Hz. Could easily degenerate into Woofiness or Puffiness if overdone.
    500-1kHz Boxy - seems to remind one of the sound in a small box-like room.
    500-1kHz Low end of Voice
    500-5kHz Power range - mid-range band which contains the 1st and 2nd harmonics of most important sounds.
    1.5-2.5 kHz Telephony - accentuating the limited bandwidth characteristic commonly associated with telephones with a roll-off both above and below.
    2.5-4 kHz Cutting - Here, "cut" means to put an incisive "point" on the sound.
    2.5 kHz Punch - Accentuating this range punches through vocals.
    3-6 kHz Presence - Anywhere from 3-6 kHz can be used to make a sound more present.
    7-10 kHz Sibilance - Dangerous "s" sounds and lots of other trashiness can often be found at 7-10 kHz.
    10-12 kHz Zizz - refers to a pleasantly biting high-end resonance (think of a "harpsichord"-type brightness found around 10-12 kHz.
    12-15 kHz Glass - A very translucent, but palpable brilliance associated with 12-15 kHz.
    15-20 kHz Sparkle - A real smooth stratospheric brilliance almost beyond hearing, but can certainly be sensed.
    Above 10 kHz Brightness - Most generally achieved by a global (shelving) EQ of everything above 10 kHz.
    Below 10 kHz Darkness - The opposite of brightness (a general lack of highs at 10 kHz and beyond).
    125-500 Hz Muddiness - Actually a compound problem: Woofiness plus Puffiness (excess low end and also low mids).
    125-500 Hz Thinness - The opposite of Muddiness (a deficiency of lows and low mid frequencies).

  5. Ear Sensitivity

  6. Dynamic Range

  7. Feedback Control

  8. Factors Influencing Clarity and Intelligibility

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Go directly to: Index -- 1) Intro -- 2) Terms -- 3) Goals -- 4) Job -- 5) Source -- 6) Mixer -- 7) Effects -- 8) Equalizer -- 9) Amp -- 10) Speakers -- 11) Understand -- 12) Set-Up -- 13) Operation -- 14) Performer -- 15) Trouble -- 16) The Rest -- 17) Advent -- 18) Sound Requirements -- 19) Light Requirements -- 20) Building Requirements -- 21) Links -- 22) Video

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