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zanner
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I have tried to look at how these, gain and dB's, relate to one another, but there seems to be nothing solid on the Internet. Perhaps I am looking in the wrong places.
The decibel (dB) is a logarithmic unit used to express the ratio of two values of a physical quantity, often power or intensity. One of these values is often a standard reference value, in which case the decibel is used to express the level of the other value relative to this reference.
In electronics, gain is a measure of the ability of a two port circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output port by adding energy converted from some power supply to the signal. It is usually defined as the mean ratio of the signal amplitude or power at the output port to the amplitude or power at the input port. It is often expressed using the logarithmic decibel (dB) units ("dB gain").A gain greater than one (zero dB), that is amplification, is the defining property of an active component or circuit, while a passive circuit will have a gain of less than one.
The term gain alone is ambiguous, and can refer to the ratio of output to input voltage (voltage gain), current (current gain) or electric power (power gain).
analogdesign said:But even simpler, dB is just a relative shorthand that is often used to describe gain. Nothing more. It is often used instead of the linear value because it leads to smaller numbers (instead of dealing with numbers like 1000 or 1 million you have 60 dB or 120 dB) and it makes certain mathematical operations simpler to do in your head.
zanner said:but there seems to be nothing solid on the Internet.
Gain and dB's are both measurements of the amplification or attenuation of a signal. Gain is a linear measurement of the ratio of output to input signal, while dB's are a logarithmic measurement of the same ratio. In other words, gain is the raw amount of amplification, while dB's provide a more convenient way to express very large or very small ratios.
No, gain and dB's cannot be used interchangeably. While they both measure the same thing (signal amplification or attenuation), they use different scales. Gain is measured in linear units, such as volts or watts, while dB's use a logarithmic scale. In order to convert between the two, a logarithmic operation must be performed.
To convert gain to dB's, you can use the formula dB = 20log10(gain). This formula assumes that the gain is measured in voltage units. If the gain is measured in power units, the formula becomes dB = 10log10(gain). For example, if the gain is 10 volts, the conversion to dB's would be 20log10(10) = 20dB.
In terms of sound, gain and dB's are used to measure the amplification or attenuation of sound waves. Gain is typically used to describe the raw amplification of a speaker or microphone, while dB's are used to describe the loudness or volume level of a sound. The higher the gain or dB's, the louder the sound will be.
Both gain and dB's can affect audio quality in different ways. Too much gain can cause distortion and decrease the overall sound quality. Similarly, too many dB's can result in clipping and distortion. It is important to find the right balance between gain and dB's to achieve the best audio quality.