Mixing Explained Article

The level of 0dB has something to do with the loudness war in my opinion. Surely is about adjusting dynamic and increasing loudness. But what to increase loudness means if not to rise up the fader and then the peaks get around -1dB and then to 0dB when distortions begin, and begin even before 0dB.
And if we continue to raise the fader of the master bus the peaks go above. Then the 0dB limit is very related to loudness war because, if we don’ to go till there deliberately to obtain distortion in order to get a certain distorted sound, every time that our peaks pass that limit because we want to make things louder we enter deliberately in the distortion zone just to get things louder. As we approach that 0 the negative effects of the loudness war increase.
As many tutorials say and also the Waves website, some Plugins don’t react very well with hot signals…and this is the reason why is not exactly the same thing to lower the fader of the master bus by the mastering engineer. Instead to keep things lower make sense, because this functioning of some plugins, both in the individual tracks and in the master bus, because often one applies at least a compressor on the master bus, I think it is prudent at the mixing stage to keep the levels at a lower level as waves site suggest. It makes sense because we now there is not a real advantage in approaching to 0 in terms of dynamic range, because in 24 bit digital recordings doesn’t maximize the signal to noise ratio, as explained in the following article

“The only advantage to recording with less headroom is to maximise the recording system’s signal-noise ratio, but there’s no point if the source’s signal-noise ratio is significantly worse than the recording system’s, and it will tend to be that way with most analogue synth signals, or any acoustic instrument recorded with a mic in a normal acoustic space. The analogue electronic noise floor or the acoustic ambience will completely swamp the digital recording system’s noise floor anyway……Analogue equipment is designed to clip at about +24dBu, so, in other words, the system was engineered to provide around 20dB of headroom above 0VU. It’s just that the metering systems we use with analogue don’t show that headroom margin, so we forget it’s there. Digital meters do show it, but so many people don’t understand what headroom is for, and so feel the need to peak everything to the top of the meter anyway. This makes it really hard to record live performances, makes mixing needlessly challenging and stresses the analogue monitoring chain that was never designed to cope with +20dBu signal levels all the time.
By recording in a digital system with a signal level averaging around -18 or-20 dBFS, you are simply replicating the same headroom margin as was always standard in analogue systems, and that headroom margin was arrived at through 100 years of development for very good practical reasons.”
Source:
https://www.soundonsound.com/sound-advice/q-how-much-headroom-should-i-leave-24-bit-recording

there is also an interesting discussion on the forum on this subject of gain staging I mean especially the oldest posts of it

I think Mattias you are definitely more prepared then me in all these matters and many of your objections were useful and correct. What I don’t understand is: if there is no reason to keep the tracks level low with peaks around -3 -6dB why plugin manufacturers and books and articles of production magazines give this advice? I don’t have clear answers and I remain perplex on the matter. I think is just a matter of safety margins….a civil engineer knows that the concrete can resist that weight, but when is building a house it doesn’t make sense to test the limits…there are safety margins, it is a common principle of every science.