Mixing gets so much easier when your processing chains are configured to deliver the same results in response to the same levels!
Gain staging and reference levels have been hot topics in audio for years. But there’s another, closely related and very important subject that I think gets overlooked: calibration.
At some point, and long before I used hardware gear myself, I understood that it makes sense to use a test tone when you want to recall an analogue mix or just to ensure that the output of an analogue device is the same as it was yesterday (believe me, that’s not a given). But the idea that calibration using tones can actually be a creative tool itself didn’t occur to me until I dove into Michael Brauer’s ‘Brauerize’ technique about six years ago. Vance Powell has likewise shared valuable workflow lessons concerning calibration.
What’s more, calibration is equally beneficial when working 100 percent in the box. There’s a reason why Brauer and his assistant went the extra mile to reproduce the analogue Brauerize calibration settings as closely as possible when he went all‑digital.
Calibration can do many things for you that are all very helpful. These are the most important ones:
- It will establish a familiar level structure that’s the same for every mix.
- As a consequence, your mixes will be very consistent level‑wise.
- It removes a lot of technical fiddling from the mix process so you can focus on creativity.
Let me give you a practical example from the studio I work in regularly. There’s lots of outboard in the racks, all hooked up to the converters and set up as hardware inserts in the DAW. Because different people use the studio to mix, I proposed establishing a fixed calibration so recalls are super easy. First, compressor parameters such as attack, release and ratio were set so as to give a great sound as a starting point — and no‑one has since felt the need to change anything. Our reference level is ‑18dBFS for +4dBU, meaning a test tone at ‑18dBFS within the DAW measures 0VU on an analogue meter. So I sent a ‑18dBFS test tone from the DAW and calibrated every compressor so that this tone generated 3dB of gain reduction, with 3dB make‑up gain applied on the output, so that they all return a ‑18dBFS signal back to the DAW. This means that when fed with a signal conforming to the gain staging and level structure we tend to work with, they give a predictable amount of compression while maintaining a consistent level. This plays nicely with the way hardware inserts work in most DAWs: if you want more or less compression, you can simply send more or less signal from the DAW, meaning that as long as no‑one changes the parameters on the hardware compressor, saving and loading a DAW session is enough to fully recall the mix.
All these calibrated devices can also give you valuable information when your gain staging is off. If a lightly picked acoustic guitar yields 6dB of compression right off the bat, it’s an indicator that it may be unusually loud. Of course that may be exactly what you want, but it’s useful to have that warning.
Calibration is equally useful if you mix entirely in the box. I suggest taking your favourite compressor plug‑ins and making presets that do exactly what I described above. Create a tone at your reference level, be it ‑18, ‑20, ‑16 dBFS or whatever you use, adjust the compressor parameters to a setting you typically use or start with, set the threshold to deliver 3dB of compression (or 1dB if you prefer) and the output level to maintain unity gain. You can even save this as the default preset if you wish.
Why would I adjust the compressor’s threshold every time to suit the mix, when I can make the mix suit the threshold?
Where I find calibration even more important is on buses, because then you essentially mix ‘into them’. For instance, in my personal hybrid home studio setup, I have all my multi‑bus compressors calibrated to give the desired amount of compression and maintaining unity gain with a ‑18dBFS stereo tone. My final master bus compressor then is calibrated to give 1dB of gain reduction with a ‑14dBFS tone and unity gain. This works super well when...