Let’s go on with a series of articles dedicated to a detailed consideration of such a complicated and multifaceted process as online audio mastering services. In this article, I am trying as closely as possible to focus on equalization used in music mixing and mastering including kinds of equalizers and their role in polishing of a finished song.
Step 1: The choice of an equalizer
When you choose the “right” equalizer, the first at the top of your head is special hardware or software processors frequently used in mixing kick drum. But the truth is that practically any good equalizer in a studio suits this goal. The key point is purity of sound, convenience in use personally for you and understanding of what you can expect from it in the context of sound. Well, that’s done it then! It will do to come down to equalization with precise realizing what will happen
next. There will be then only your creative decision. I can also mention a spectrum analyzer out of supplementary functions. It will simplify the process for both an experienced online mixing engineer and particularly a beginner for whom it won’t be excessive indeed. There is certainly a possibility of equalization in MS mode as well.
Be careful! In spite of the availability of stock DAW equalizers pro engineers point out that they are insufficient at the mastering stage due to evident phase shifting and, consequently, sound distortions. They are always at hand and don’t practically burden the processor so it’s their only advantage. But the pay for CPU usage reduction with simple algorithms is clearly audible phase shifting. Such equalizers are good only at the music mixing services stage and even of accessory elements. Personally, I would recommend Fabfilter’s Pro Q. It is a perfect choice for a beginner with an enormous potential of growth to a professional musicengineer.
Step 2: Linear or not
Now in more detail about the linear phase mode and all the pros and cons of use of such equalizers in audio mixing and mastering. First, far from every equalizer in your favorite DAW has such an option that’s why in most cases it won’t suit final track processing, actually mastering. As an exception I can name a linear phase equalizer as part of Logic. The algorithm of its work has already been indicated in the title so you can easily use it in vocal mixing tricks. To choose an appropriate EQ out of non-stock ones is a lot easier as there’re a great deal of developments towards linear phase EQ processors. There are a great many equalizers suited for it, the same Fabfilter’s Pro Q which allows you to work in both the linear mode (herewith you can pick out the length of delay out of five options offered, starting with minimal to the highest possible) and in the ordinary one with the maximum economy of CPU (ideally for mixing).
The phase shifting of its own accord isn’t bad, and non-linear equalizers are often used in audio mixing due to specific coloration added to the sound. I would name Ableton’s stock EQ as a typical representative. It has zero gravity for a processor and specific focusing on upper midrange. But in most cases this approach doesn’t suit audio masteringgoals so you’d rather make a choice towards linear phase equalizers. Thanks to special algorithms they add absolutely transparent sound in online mixing mastering services with EQ and play more technical role in cleaning a track from all excess stuff without applying its own coloration. We don’t care about resource-intensity and delay as most of processing has already been done by an engineer.
Step 3: Physical modeled equalizer plugins
As you know, the difference of hardware devices from purely digital ones is in special character of work of transistor and tube chains which add a little saturation and a number of random anomalies to sound. All this makes out the “fatness” and the “warmth” of music for which you like the sounding of analog devices very much.
The professional loud mastering process is so multifaceted that you can’t categorically recommend using one or another kind of devices in different cases. First and foremost you should ask yourself what exactly you expect from the process and of what the track that sounds now in your studio comes short.
If audio requires a strictly technical approach to music mixing, the choice will be towards digital equalizers with their absolutely transparent sounding. If the personal taste of an engineer requires of mixing some extra character and warmth, and possible a little of grit, physical modeled EQ plugins are definitely the only technique to achieve a desired goal. After all, concepts of “correct” and “incorrect” in music are quite subjective, and the best tactics is that one which gives the most exciting sound.
It’s just worth separately emphasizing linear phase equalizers as another alternative. They are often used in online music mixing with equalizer exactly due to their practically invisible influence on the sound and absence of their own coloration, such a surgical instrument of an mixing service engineer. If you doubt your choice, you’d rather take a liner phase equalizer as transparency is a first-priority quality expected by clients.
Step 4: Less is more
Since the lion’s share of the work to add some coloration and depth to music has been done during mixing services, an engineer should work on the principle “Less is more”. It’s first of all subject to the amount of equalization – considerable frequency enhancing and attenuating will break the balance preliminary built in a music studio. When an mixing background vocals engineer enhances or attenuates certain frequency more than by 3–4 dB, he must clearly understand the goal of this action. Otherwise the mix will work out rough and with broken and sharp sound of the frequencies enhanced for the sake of a vague goal.
Is it really necessary to intervene in mix sounding so extremely? If the reply is “Yes”, there’s more likely an error in mixing, and you should solve the problem with the preceding step. If the sound of the track doesn’t satisfy you, it is always more appropriate to tinker at flaws than use extreme processing at the mixing services stage.
Turn your attention to the peculiarity – special mastering equalizers have a limited boosting and attenuating range for each frequency range. In fact, even the stock provided by a manufacturer is excessive as in practice the range equal to 2–3 dB is exactly what makes sense to use in music mastering. When an audio engineer works with these values coupled with small values of Q parameter (let’s recall that in this case the lower Q is, the wider processed frequency band is), he is capable of carefully building tone and balance of the track in sort of bold and soft strokes by slightly emphasizing the idea initially put in it at music mixing mastering with equalization.
Step 5: Q detailed
Since a considerable intervention in track balance isn’t the goal of mixing, the music value of unreasonable frequency peaks is close to zero. It means that a audio mixingengineer should work with small values of enhancing and attenuating and wide bands, in other words, with small values of Q parameters. It will allow you to make changes at once in groups of instruments included in equalization. This approach is preferable in mixing as it gives the maximum of transparency and lets you achieve a lot more cohesion of song elements only by emphasizing the main music idea.
Step 6: Low cut filtering
This is a super important step in equalization about which beginners forget. No matter how perfect an acoustic system is, even in the largest out of them the frequencies in the region of 30 Hz and lower are a weak spot where music loses its legibility and energy. As for most of near-field and even mid-field speakers, this spot displaces up to 40 Hz and higher. Along with the particularity of our hearing in the range of low frequencies it is highly recommended to filter sub-harmonics lower 30 Hz during audio mixing services, in extreme cases from 25 Hz and lower if you reckon that in this way the result will be more musical.
The energy of low frequencies is huge and fades out a lot more slowly than others. It can affect dynamic processing of a track – even if, personally, you can’t hear anything like that. Unnecessary splashes of sub-frequencies will affect subsequent processors in a processing chain and cause distortions. Herein this mix element brings only mud and illegible humming for our ear. On disposing of it at professional online music mixing with EQ, the result sound will only benefit.