What is Gain in Audio? Level, Volume and Signal Strength Explained

If you’re just getting started with music production, you may have heard terms like gain, level and volume used to describe signal strength.

But are they all the same? What does each mean exactly and how do they affect your workflow?

The answer isn’t always simple if you don’t know the concepts behind them. Luckily, there’s nothing complicated about audio gain once you break it down.

In this article, I’ll explain the exact meaning of the term and explain the different ways it’s used in music production.

Let’s get started.

What is gain?

Gain in audio is a term for the amount of amplification applied to a signal by any process that increases its strength. It’s measured in decibels, or dB for short.

A good way to think about gain is as the difference in signal strength between the input and the output of an audio system or processor.

If that sounds complicated, don’t worry. For most producers, gain comes into play at a few key points in your workflow.

I’ll go through a few examples to help you understand.

Preamps, signals and your audio interface

The simplest way to explain gain is to follow the signal path for a typical sound you record with your DAW.

A good way to think about gain is as the difference in signal strength between the input and the output of an audio system or processor.

A common example is when you use a microphone to record a singer or an instrument.

Microphones work by converting vibrations in the air into a weak electrical signal. When the sound waves reach the microphone’s element, the changes in air pressure turn into changes in voltage, which represent the sound.

This version of the signal isn’t strong enough to record directly. It needs to be amplified several times over to reach a healthy level for your audio interface.

Gain is the term for the amount of amplification introduced to the signal by the preamp. In this situation, your audio interface’s mic preamp is the amplifier that increases the strength of the signal.

Even though it seems like a single device, a typical audio interface includes a set of different components for bringing signals into your DAW.

After the preamp, your sound gets converted by a digital-to-analog converter so it can be stored as a file on your hard drive.

Gain in your DAW

Most engineers use the term gain to refer to processes that occur in the analog domain before your signal reaches the DAW.

But there are still plenty of places where gain comes into play in your session files.

One clear example is when using a compressor. If you need some background on how compression works, head over to our guide for a full overview.

But to recap the basics, a compressor reduces the level of a signal when it passes a certain threshold. They’re used in music production so that loud and quiet parts of the signal can be heard equally.

But reducing the signal level with even light compression naturally makes it quieter due to the compressor’s action.

To get it back to the same overall volume, compressors typically include a makeup gain control to boost the signal back up.

You can think of this as a digital version of the same process I talked about earlier.

In fact, gain in general refers to any amplification of the signal that increases its strength and overall volume.

Hot tip: Unlike analog gain, increasing signal level in the digital domain doesn’t cause side effects like increased noise floor. But that doesn’t mean you should record weak signals into your DAW. The best approach is to manage headroom and gain staging together to stay in the sweet spot for both analog and digital.

Does gain also mean distortion?

If you play guitar, you’ve probably used gear with a gain control that increases the distortion and saturation in your signal.

You’ll see this on drive pedals, amp controls or even guitar plugins.

These knobs are often labelled “gain” because they create distortion by amplifying the signal beyond the clipping point.

The big difference is that this type of gain stage is followed by a master volume control that brings down the level overall.

Even though it’s related to the same process, gain doesn’t mean distortion in most other audio situations.

It’s true you can create desirable saturation by driving some analog mic preamps and lowering their output with a trim control. But it’s much more common to record clean signals by applying just the right of gain and preserving headroom at each step.

If you need a primer on the basics of good headroom and gain staging, check out our in-depth guides to the subject.

Gain, volume and level

If it seems like there are a lot of different ways to refer to the volume of a signal, you’re right.

But in fact, each of them has a specific meaning that’s worth understanding.

As I explained above, gain refers to signal amplification.

On the other hand, volume means the perceived level of a sound. After all, a meter in your DAW can only give you a representation of a sound based on its electrical qualities.

How loud that sound seems to you differs because of the way humans perceive sound.

For example, it takes more signal energy to produce the same perceived volume for low frequency sounds compared to those in the presence zone (2 to 5 kHz) where your ears are most sensitive.

You can still express perceived volume in units in order to make comparisons, but you don’t need to worry too much about that in your DAW.

Instead, the relative balance of each track in your session is best defined by the term level.

Signal level is measured in your DAW using two methods that describe different qualities—Peak and RMS.

If you want to learn more you can find the full breakdown of these terms in our guide.

For the short version, Peak level means loudest single moment in a signal, where RMS refers to the average intensity over a period of time.

Signal level is measured in your DAW using two methods that describe different qualities—Peak and RMS.

peak level meter example

rms level meter example

Your DAW meters usually include a mix of both to give you the best idea of your signal at a glance.

Amplifying your signal

Gain is a fundamental concept in music and audio production.

It’s important to know the exact definition to get the best results from your gear.

If you’ve made it through this article you’ll have a great start for capturing sound with your audio interface and adjusting levels in your DAW.