The waveform levels or states can be interpreted in a number of different ways. Reading the states in their binary form is impractical, so the states are mapped to different scales that are more human-readable. These include a simple amplitude scale, a percentage scale, and a decibel scale. As the figure shows, a 1.0 amplitude level is the same as a 100% level and a 0dB level. Figure: Volume Scales
Volume Scales

The amplitude scale simply maps the states to a linear range of -1.0 to +1.0, with zero being silence. The amplitude typically is given as a positive value when used in effects.

The percent scale is 100% at the maximum and 0% at silence. It is essential the same as the absolute value of the amplitude scale converted to a percentage by multiplying by one hundred and adding a percent sign. Sometimes a negative percentage is used, such as in the effect, to invert the waveform.

The decibel scale (specifically ) is unusual in that it is 0dB at the maximum peak level and negative infinity at silence. It is a logarithmic scale, which is closer to the way human hearing perceives sound levels. You'll notice from the above figure that there are no positive levels. Levels below the maximum are negative. Only values above the maximum are positive (not shown) and such values may cause . When changing the volume, positive values increase the level and negative values decrease the level.

Levels shown in most visuals are and not .

Use the equation below to convert a decibel level to a percentage level. Decibel Equation

When setting the volume in an effect, the value may be interpreted as a relative level or an absolute level. When changing the volume, it is usually relative. When specifying a threshold, it is usually absolute. Relative changes are cumulative. So if you apply a volume change with 0.5 amplitude (50% or -6.02dB), then the amplitude decreases to half its current level. If you apply that change again, then it decreases to one quarter of its original level. In other words, the change is relative to its current level. Given an original amplitude of A, the first change yields a result of A x 0.5 and the sample is replaced by that value. The second change takes that value and multiplies it by 0.5 again, so we get the final result of (A x 0.5) x 0.5 or A x 0.25. Most of the effect settings in GoldWave are cumulative. For relative changes, using 1.0, 100%, or 0dB does not alter the sound at all.

Absolute levels are user for thresholds, such as in , or in rare cases were the absolute level is set directly, such as . Absolute changes are not cumulative. If you maximize the sound with 0.5 amplitude (50% or -6.02dB), then that is what the peak level will be no matter how many times the effect is used. For absolute changes, using 1.0, 100%, or 0dB may alter the sound if it is not currently at that level.