When working with amplification equipment, we often misuse the terms gain, loudness, volume and level etc. Maybe that’s because we often see them or at least 2 or 3 of them on the same equipment. However, these terms are interrelated but have different meanings and that can easily be confused into one another.
Understanding each of these stuffs in order to make a good sound from our equipment is very important. But first, let us define and understand what audio gain is.
Gain is one of the most difficult terms to define, especially because it is used a lot in different aspects, not just in the audio world. But the use of this world is just quite simple which means an increase in some kind of a value.
For example, you can have voltage gain, power gain or current gain; and they all show an increase in those respective values. In music, when referring to gain, we refer to transmission gain which means the increase in the amplitude of a signal from an input to an output port.
This increase is often expressed using the unit dB (decibels). On a clearer note, this could be the increase in the power of the signal from your microphone or electric guitar before it is transmitted to other electronic components such as the amplifier.
The Use of Gain
Usually, the most common place where you can see gain control is in these 2 places. One of them is on your guitar amp and the other one is on your PA or mixer board. The terms both mean exactly the same thing but they serve different purposes in each of the aforementioned electronics.
On a guitar amp, the main intention of the gain is to create distortion which accentuates your guitar playing skills. However, as a special tip for novices: they shouldn’t take their distortion on 10 all the time. They may think their sound is ridiculously awesome, only to think that they should take it down to 5 or 6 because the sound they produce is horrible.
On the other hand, on a mixer board, you’ll spot the gain on the top of the board. It is usually the first control that a raw mic signal sees, and works by boosting the signal to the right level for the entire controls to work properly.
Basically, you’ll want this gain high enough to bring up the signal level, but not too high that you’ll already get distortion or clipping in the signal. Because of this, many mixer boards come with a “pre-Fader Listen (PFL) button to let you see the signal strength through the LEDs of the board.
What is Volume?
The difference between volume and gain usually confuses many people. Generally speaking, a gain is a control of what is coming ‘in’ into a piece of gear while volume refers to the control of what is coming ‘out’ from a piece of gear.
Typically, the volume can be controlled using a knob or a fader and it also affects the output of the mixer to whatever bus it is assigned into, whether it is an aux send, a group or a master bus. When you turn up the ‘volume’ knob on your amp, it just simply means you are adding the amount of power to increase the signal used by the amp.
How about Gain Staging?
Another term that confuses people is ‘gain staging.’ What does this mean? Is it important?
Well, gain staging makes sure that the level of the signal right at each part of the signal chain is ‘gained’ or adjusted properly. This is very important to understand especially that we are right in the digital age now.
Using analog setups, overdriving the input gain results (not always) in that pleasing distortion sound or that highly-sought after ‘saturation’ of the sound. Gain staging is one of the most important things we can do to maximize the signal and noise ratio of our PA or studio setup.
Overall, in simplest terms, the volume is literally used to adjust the loudness of the sound signal as we perceive it through our ears, whether we are using headphones, speakers etc. Meanwhile, a gain is used to alter or adjust the signal strength, whether it is a mixing board, a signal sent to magnetic tape or within the software DAW etc.
To help you differentiate the two, here is the simplest way to remember it:
- Gain- internal voltages
- Volume- perceived loudness
It is inarguably clear that these two terms are inter-related that’s why it is very easy to be confused by them.
In clips, audio gain generally refers to the volume or input levels in clips. Meanwhile, volume generally refers to the volume or output level in tracks or sequence clips. Audio gain or volume levels can be set to make more consistent levels among tracks or clips and to change the levels of volume of a specific track or clip.
However, we should keep in mind that if you set the level of an audio clip too low when it’s digitized, then increasing the volume or the gain could also amplify the noise. To avoid this, follow the standard practice of digitizing the source audio or the practice of recording at an optimum level to allow you to concentrate on adjusting the track levels.