What's the Difference Between Amplification and Gain?

[JJ91]

Hello,

I can't figure out what's the difference between the two:
Gain - how much the amplitude of the signal was increased/decreased
Amplification - how much the amplitude of the signal was increased/decreased

If we take a basic inverting amplifier circuit:
http://alturl.com/39n78

We can see an amplification of signal by 3 times from 5V to 15V
This is equivalent increase of 300%
300% to dB would mean a gain of 4.77dB according to http://www.lightmachinery.com/percent-to-dB-conversion-calculator.php

Is gain (dB) simply an amplification rate in different units?

Thanks.

 

[skeptic2]

First of a gain of 3 from 5V to 15V is not a 300% increase, it's a 200% increase. Yes, the calculator you reference does show that a gain of 3 is 300%, but that's not the same as a 300% increase. A 100% increase would be an increase from 5V to 10V. Second the dB calculator is calculating power increase not voltage increase. Power gain varies as the square of voltage increase. A voltage gain of 3 would have a dB value of 9.54 dB.

Gain is often expressed as dB so the gains of multiple stages of other elements can be added together instead of multiplied or divided. It's not different units, it's a different mathematical operation. For voltage gain you should use the formula 20 * Log(Vout/Vin).

 

[davenn]

amplification is what is "occurring ... the gain figure quantifies the amount of amplification occurring

...Gain is often expressed as dB so the gains of multiple stages of other elements can be added together instead of multiplied or divided. It's not different units, it's a different mathematical operation. For voltage gain you should use the formula 20 * Log(Vout/Vin).

and to follow on from skeptic2's formula above ...

power gain = 10 * Log (Pin/Pout)

Dave

 

[JJ91]

Super simple, thanks.

 

[alphysicist]

Hello,

Thank you for your question. To answer your question simply, yes, amplification and gain are essentially the same thing. Both terms refer to the increase or decrease in amplitude of a signal. However, there are some technical differences between the two terms that are worth noting.

Amplification is a more general term that refers to any increase or decrease in the amplitude of a signal. It can be used to describe the increase in voltage in an electronic circuit or the increase in volume in an audio system. Gain, on the other hand, is a more specific term used in the field of electronics and signal processing. It is a measure of the ratio of output signal to input signal and is usually expressed in decibels (dB). In your example, the gain of the amplifier circuit would be 4.77dB, which means the output signal is 4.77 times larger than the input signal.

In summary, amplification and gain are similar concepts that describe the increase or decrease in amplitude of a signal, but gain is a more specific term used in electronics and is measured in decibels. I hope this helps clarify the difference between the two terms. Let me know if you have any further questions.