Gain staging = how to do it


Gain staging

They teach this a lot in recording school, and engineers of all stripes love to talk about it endlessly. But what is it? The best way to understand this fundamental mixing concept is to just do it - but then how do you know if you're doing it "right"? 

Stay tuned - below we'll explain what gain staging is for, how to properly monitor levels during mixing, the importance of using a VU meter, and much more. We'll stick to practical procedures and explain a lot of the necessary technical jargon along the way. Let's get straight to it! 

What is “gain staging?”

Gain staging is the optimal balancing of a signal as it moves through processing. When you adjust the volume of a signal so that it’s not too soft, not too loud, but just right 

Here are the basic terms to get comfortable with when talking about gain staging: 

  • Signal: Your signal is whatever instrument or desired sound you are recording or mixing. A signal can be anything: a vocal, a drum, a texture, a sample, whatever you’ve got. 
  • Gain: Audio gain is the ratio of output power to input power. In the context of plugins and audio equipment, “gain” is often used to denote the input volume. Gain is measured in logarithmic decibels (dB). 
  • Level: Level is the output volume of your signal. In DAWs, you control the final level of each track using a fader. Level is measured in logarithmic decibels (dB) and unity gain is 0dBFS.

A solid understanding of gain structure will help you become a better mixing engineer and prepare tracks for mastering. Careful gain distribution can lead to punchy and effective mixes, while poor gain distribution can result in bloated bass or a lack of dynamic range. 

It's important to think about gain staging at every stage of working on a track, from recording to mixing. Every time you use a plug-in or external device, you're probably changing the gain of the signal in some way. You want to have a balanced amount of gain as you transition the signal from one plug-in to another. 

At first this may seem like a difficult concept, but once you get the hang of it, gain stepping becomes something you do automatically every time you record and mix.

What is "Right" gain staging? 

How do you know if you have the correct gain set? The ultimate goal is always to make your music sound good. This can be a subjective goal, so you have to take into account the context of the music you are creating. 

Are you producing modern rap or pop music? Then the most important parts for you to spend time gain staging are probably the sample kick and bass. Setting them up will help you relatively determine the levels of your vocals. 

Maybe you're working on a metal track where the guitars are especially important. Here, gain staging starts at the recording stage. The amount of gain going into an amp determines how that amp breaks down and how it will sound when recorded. 

It's helpful to think of everything in terms of inputs and outputs. Analog devices and digital reproduction of analog circuits affect the signal dramatically differently when you increase the input volume. The output volume - or level control - is used to adjust the volume of the signal going to the next device. 

Going through this process with each of the tracks to balance them all during the mix process is called gain staging. The goal of gain staging is to get the best mix of your track.

Gain staging basics 

To understand gain staging is to understand signal flow!

  • Signal flow: The signal flow is the complete path your audio takes as it enters your computer, runs through your audio interface, gets processed by plugins, and then exits your speakers. Every track has its own signal chain, and all tracks eventually lead to the master fader.
  • Pre-fader/post-fader: These can be confusing terms because they are descriptors, not actual faders. When a control is pre-fader, the fader or send is controlling the volume of a signal as it heads into a processing chain. When a control is post-fader, it’s controlling the volume coming out of the processing chain.
  • Master fader: The final fader at the end of all the signal chains on your console or DAW. The master fader controls the final output volume.

  • dBFS : stands for Decibels Full Scale and is the unit for digital audio loudness level. In most DAWs, 0dBFS is the volume at which the master fader is at unity gain. Anything above 0dBFS results in digital distortion in your exported mix.

here are some general guidelines that will help you wrap your head around it:

  • Always check your track levels. Whether you are building a song from scratch or importing stems into a mix session, make sure none of your tracks are peaking. 

  • Stay away from the main fader when mixing. If clipping occurs on the master (i.e. the volume of the combined tracks is higher than 0 dBFS), you must mute some tracks. Playing with the master fader while mixing will only cause you bad mixes, bad decisions,and headaches later.

  • Figure out what the loudest or most important part of your song is. Get that element to a suitable volume, and then work around it to determine how loud everything else should be relative to it.

Headroom and clipping 

Audio nerds love to throw around terms like “headroom,“ “distortion,” and “clipping” when talking about gain staging. (We say this with love, as audio nerds.) But what do these words actually mean?

  • Headroom: Headroom is the amount of space you have between the “peak” volume point of your mix and the point at which you begin to get distortion. (If your mix peaks around -18 dBFS, you have 18 dBFS of headroom.)

  • Distortion: In signal processing, “distortion” is any alteration of a signal. (An EQ is technically a form of distortion.) However, in practice, the word “distortion” is used to describe the sound of an audio signal exceeding the designated “maximum” volume of a circuit.

  • Clipping: Clipping is the more accurate term for what we generally call “distortion.” People often say “clipping” to describe when a fader is in the red. In the digital realm, clipping occurs at 0 dBFS.

Clipping can be both “good” and “bad.” “Good” distortion and saturation is the whole appeal of vintage preamps or guitar overdrive pedals, which lend harmonically pleasing distortion to audio signals. “Bad” clipping can occur when you have too much gain going into a plugin with limited headroom.

  • Your song will eventually have to leave the DAW environment and be exported in a 24-bit file, which will result in unwanted clipping if you’re pushing past 0 dBFS.

The best gain staging practice is to avoid letting any faders go into the red when mixing, regardless of lack of audible clipping.

Meter and measuring loudness

As in other parts of mixing, we use our ears, not our eyes, to get the volume. Still, peak and volume meters are essential for tracking elements and keeping perspective when working on a mix. 

Metering helps you get a quick overview of the mix level before you even let it out of the speakers. After all, you can raise or lower the volume of your speakers at any time - so how else would you know if your track is loud enough, or if your speakers are just overdriven? 

There are several kinds of "loudness" measurements to understand when gain staging. Different meters will give you different metrics for measuring your gain staging:

  • VU meter: The VU (volume unit) meter was originally a mechanical device for measuring loudness that was designed to match the way human ears perceive sound. Today, you can use VU meter plugins in your DAW.

  • Peak meter: The peak meter marks the loudest point of a signal in dBFS. Generally, you don’t want your peaks to exceed 0 dBFS.

  • RMS meter: RMS stands for “root mean square.” The RMS meter measures the average sound level in dB, similar to a VU meter.

We recommend you use VU meters in addition to peak and RMS meters when mixing and gain staging, because headroom is built into VU meters by design. VU meters let you gauge and adjust loudness without having to mess with your track faders. 

The dBFS to VU conversion is not one-to-one, because dBFS is digital audio loudness and VU is a real-world measurement. 

Now that you’ve got some knowledge on gain staging and how to do it effectively, the best way to improve is to just do it. We’ll leave you with some best practices, recommendations, and concepts to remember as you dig into it:

  • You can always turn it up later. Better to be on the slightly softer side and leave yourself more headroom to adjust later on than to introduce unwanted noise or print a mix too hot.
  • Use buses. A bus track is essentially a group track, taking multiple signals and routing them to the same audio channel to process them together. This lets you control the sound and overall level of multiple signals with one channel.

  • Get your kick and bass levels set early. Here’s a practical tip for your next mix: Pull all your faders down and pull up your kick and bass. Balance each level and try to get it sound around where you want it, aiming for peak -12 to -6 dBFS on the mix bus. Now go from there.

  • Record in 24-bit. With disk storage growing cheaper by the year, there’s no excuse not to record in 24-bit audio anymore. You get more headroom with no downside.

  • Careful with analog emulation plugins. Because analog circuit emulations all work differently, you should keep a special ear out for how your gain affects how each plugin affects the signal.

  • A/B comparison

  • These are by no means hard and fast rules. If you do something "wrong" and it sounds good to you - then it's not wrong! But if you find that you're not getting as much as you'd like from your recordings or mixes, thinking more about gain stepping can help you improve your sound.

Have fun at the next mixing 

don't forget, gain staging :D :D :D