Everyone who has been busy in the music industry for a while is familiar with the concept “mastering” and knows what this process includes.
But let’s be realistic…
Although the mastering engineer indeed estimates audio materials from the perspective of these aspects in order to bring in defined enhancement, genuine mastering of a perfectly mixed track is like a tender kiss, processing with a minimal and very subtle interference before you get the song released.
Personally, for me, the core value of mastering is the fact that dynamics, space, balance and track energy are assessed by a professional with an absolute fresh perception. His ear hasn’t gotten used to each song nuance and can detect subtle details lost by a mixing engineer.
Unfortunately, this situation is from the sphere “this is as it should be” whereas in actual practice the producer often expects the mastering engineer to be able to correct the mixing faults and the damages caused by insufficient acoustic treatment coverage in a room what successfully condemns him to the way of compromises.
The best way to achieve desired sound is indeed to put it already at the production stage and to emphasize it with competent mixing.
So, mastering has no power to correct the following:
Case 1. The balance of instruments
Careful multiband compression on the master channel is surely applied quite often, and it helps to place sounds in the space much better.
Often, you come across some recommendations sort of “If drums stick out excessively, apply the compression with a short attack and a fast release to equalize their balance with other sounds.”
But it’s sooner from the field of an inconsiderable correction of the mixing engineer’s error.
When it comes to serious faults, this method is inoperative.
Case 2. The lack of stereo width
This is the truth as stereo image processing of a track falls into the mastering engineer’s competence. But over again, his role here is more technical.
As in the case with equalization, the engineer primarily removes excessive things, namely the stereo element of sub-lows…
Personally, I finish on it. Everything that I wanted to add to the song in regards to sound width I do when I mix it.
The only exception is when I apply a stereo expander to emphasize the difference between verses and refrains. If the track sounds narrow, the use of stereo expanders with drastic settings will bring about only phase distortions.
You’d rather come round to mixing and work with panning.
Case 3. The character of key sounds
If drums are dull, and guitars lack of density or vocals hardly cut through other mix sounds, you shouldn’t expect a miracle of mastering.
Yes, multiband compression with a long attack can put life into drums a bit but just a little and perhaps with side effects on other mix elements.
Case 4. Tonal balance of instruments
The finished mix is like a puzzle of elements each of which has to play its role clearly. Bass has to give base and depth due to low harmonics.
The role of a kick drum is the “punch” that enhances the bass attack and gives a pulse to the entire track.
Distorted guitars saturate the track with fat mids. And so on.
Depending on that, every instrument has to be processed to emphasize its intended purpose.
This is exactly the recipe of an “ideal” sound. If it has been broken, mastering has no power.
Case 5. Limited frequencies
For the finale, I’d like to bring the attention to such a detail as special mastering equalizers that have limited enhancement/attenuation ranges for every frequency band.
Yet even this holds out in plenty since 1–3 dB of enhancement/attenuation will be enough for the engineer during mastering of a well-mixed track.
All the rest is an attempt to correct somebody else’s error and a way of compromises where the advantage in one aspect is achieved at the expense of the overall sound transparency.