Sound Power - Sound Power Measurement

Sound Power Measurement

A frequently used method of estimating the sound power level at a source is to measure the sound pressure level at some distance, and solve for :

L_\mathrm{W} = L_\mathrm{p}-10\, \log_{10}\left(\frac{1}{4\pi r^2}\right)\, If the source is in free space

or

L_\mathrm{W} = L_\mathrm{p}-10\, \log_{10}\left(\frac{2}{4\pi r^2}\right)\, if the source is on the floor or on a wall, such that it radiates into a half sphere.

The sound power estimated this does not diminish or increase with distance, unless reflections are present.

Read more about this topic:  Sound Power

Famous quotes containing the words sound, power and/or measurement:

    “the children call, and I
    Thy shepherd pipe, and sweet is every sound,
    Sweeter thy voice, but every sound is sweet;
    Myriads of rivulets hurrying through the lawn,
    The moan of doves in immemorial elms,
    And murmuring of innumerable bees.’”
    —Alfred Tennyson (1809–1892)

    “Thy blood and virtue
    Contend for empire in thee, and thy goodness
    Share with thy birthright! Love all, trust a few,
    Do wrong to none. Be able for thine enemy
    Rather in power than use, and keep thy friend
    Under thy own life’s key. Be checked for silence
    But never taxed for speech.”
    —William Shakespeare (1564–1616)

    “That’s the great danger of sectarian opinions, they always accept the formulas of past events as useful for the measurement of future events and they never are, if you have high standards of accuracy.”
    —John Dos Passos (1896–1970)