What can you gain from gain staging?
Whether you're recording or mixing, gain staging is one of the most important jobs you have as an engineer yet it is shrouded in mystery to beginners. Understanding gain staging can take your recording and mixing to a whole new level and allows you to have a clean mix without worrying about clipping.
So what is gain staging?
There is a difference between gain staging in the analog domain and in the digital domain. The discuss about analog gain staging is for another time so, this may be a handful but the simplest way to explain gain staging in your DAW is the following:
Optimizing the input signal in order to maximize the signal's strength whilst reducing noise and distortion with the right amount of headroom.
It sounds simple enough and it really can be but, once you start adding plugins in your DAW, you'll need to keep this in mind every step of the way. It's really about understanding how each of your gear affects the signals output to your advantage so you can work more efficiently and professionally.
And what is noise?
A signal that is noisy is not necessarily loud. Noise is the unwanted sound as part of the incoming signal. If you cranking an amp's gain up to 11, you will surely understand what noise is before you have even touched a string even at low volume. In the days of analog, the noise was usual generated through the magnetic tape but the Digital Audio Workstation eliminates a lot of noise generated.
When you're recording multiple tracks, setting the signal-to-noise ratio is really important. If you have too much noise on every track you have recorded, it will all build up and eventually become noticeable in the mix.
And what is this headroom?
Headroom is the space between the highest point of the signal's transient, the loudest peak, and 0dB. Leaving headroom is crucial because leaving enough headroom means your track won't clip and distort.
Gain stage correctly and you'll have plenty of headroom and very little noise.
So how and where do we do this?
Gain Staging during recording
As mentioned, at every step of the way, you need to accommodate for the source's loudest peak yet leave enough headroom to avoid clipping. No better place to start is at the source of the source. The microphone. Regardless of how you set up your microphone, your preamp gain needs to be set accordingly. If the gain is set too low, your recording will be too noisy. If you've set the preamp gain too high, you'll get distortion.
A great way to start is to ensure that your DAW's faders are set to “Unity Gain” (0dB) as this gives you the right amount of resolution and allows you to monitor how much headroom you have got. When setting the gain of your preamp, you will want to aim between -18db and -10db to ensure that you have a solid signal. There really isn't anything to gain from setting your signal levels super hot so, although it isn't a standard, take this as a rule of thumb.
Set this right and you're partway there. Some professionals need not move the faders during the mixing stage because they set the gain stage correctly.
Gain Staging through plugins
Although you've eliminated the issues through proper gain staging during recording, the problems don't end there. When using plugins, you're most likely using plugins that model analog gear like EQ and compressors.
Analog gear has a “non-linear” behavior which means that, should you be cranking them, you will have more saturation and distortion which can be great for creativity but, if used too much, can lead to your mix sounding brittle.
Again, use the rule of thumb to aim the signal at -18dB. You will then be hitting the master bus with great resolution and plenty of headroom.
In conclusion, always be mindful and ensure your gain staging at every point in the signal chain. Once you have practiced this enough, it will become second nature to you and you'll look back thinking how could something have been so mysterious in the first place!