Let's talk about mastering music. This is a concept that many beginners and most laymen often have no idea about, and often can't differentiate from mixing, which is an entirely different craft. So first, let's get it straight: what is the difference between mixing and mastering? Mixing is the process of taking all of the individually recorded (or produced/sampled) tracks in a song, and adjusting / manipulating them to create a full stereo mix, controlling the balances of the elements and the frequencies in the track so that the presentation of the song is sonically as good as it can be. However, before releasing the track, the stereo mix is often sent to a mastering engineer (or mastered by the mixer). The mastering process involves usually just one audio track, the stereo mix, and the purpose is to get another set of ears on it, or one final check before releasing it, making usually very subtle adjustments to things such as compression, tonal balance, overall loudness etc. in order to ensure that the final release will sound as best as it can across all possible listening environments.
Where Should I Master & What Speakers or Headphones Do I Need?
When you start mastering a song, you'll want to make sure you have fresh ears (not tired ears from a long session of mixing or mastering other songs right before you began), as well as a good listening environment that you're familiar with. Familiarity being the most important thing here, because you'll be more likely to intuit if something sounds lacking or off if you're used to listening to music there, but also ideally it's somewhere that you can hear the full frequency spectrum, so assuming you haven't built out a mastering studio, something like a nice pair of headphones might be better than a subpar speaker in an untreated room. In any case, you'll likely want to reference it on multiple listening devices to be certain.
My personal headphone recommendation is the Beyerdynamic DT1990 Pro, for a good quality headpohone on a reasonable budget. There are plenty more out there, and you can get even better quality if you're willing to dish out over 1 or 2 thousand dollars, which is still more affordable than building out a room plus getting high quality speakers. I personally don't have an exceptional speaker set up and I only use the ones I do have as a reference point rather than to mix or master off of them, so I cannot make educated recommendations on which speakers to choose. I can say, however, that with speakers, the most important thing is actually going to be your room and acoustic treatment will often go further than upgrading your speakers.
During mastering, ideally you'll want to reference two things. One of those is the final mix, you want to make sure you're not ruining the mix, and if you're mastering for someone else you really want to make sure you aren't changing the sound too much from the final mix, unless they expressly say otherwise. Ideally you want the master to still sound like the mix in terms of the vibe and the relationships between things, you just want a little extra polish and a little extra care to make sure it sounds good on any speaker or headphones. Maybe a little more compression, and also make sure the volume is consistent with other songs in the genre. This is where the second referencing item comes in: a similar song in the genre that's well mixed and mastered. Trying to make sure the overall quality of the sound and the loudness in particular are comparable is a major component of mastering.
Mastering Plug-Ins I Like To Use
This is really subjective and there are many more experienced mastering engineers than I on the subject, but if you're just diving into mastering and don't know where to start, this list of plug ins and how to use them can help get you started.
Pro Q 3 - This EQ plug in from FabFilter is a great way to help shape the tonal balance and give little boosts or cuts where needed. With mastering, it's typical to be very gentle with an EQ, not making EQ moves over around 1-2 db, but it's going to be situational and you'll get a feel the more you do it. If you are mastering your own track, you can certainly decide to make bigger moves if you want to make a bigger creative choice in the tonality of the song. For example with some lo-fi tracks of mine, I've decided at the last minute to shelf over a 5 db cut in the high end to make the track darker. You can really use any EQ, and some engineers prefer using analog modeled EQs to give the track a certain color / saturation. The Pro Q 3 is just the one I use because I like the interface and it's easy to use.
Black Box - This saturation plug in from Brainworx is a fantastic plug in for beefing things up without reducing the quality or introducing clipping/artifacting. It has a saturation and two distortion models which can be used either very gently or very aggressively, and in comparison to many others, it leaves the sound pretty clean when you run it through the plug in. The way to use the distortion is a little different, the knobs start in the middle, which equates to completely dry sound, or 0%, and you can turn the knob in either direction to affect the sound. I'm not sure what is happening when you turn it left, but I typically turn the knob to the right just fairly gently and then turn the output down to gain stage. From there, you can turn the plug in on and off to compare the audio. Try to make sure you aren't changing the actual output volume in dB so your ears aren't being tricked by the loudness.
Shadow Hills Mastering Compressor - This plug in contains two compressors in one. The interface looks really complex when you first look at it, but just know that the only knobs you have to worry about are on the left side. The right side is for if you are compressing each side differently using the dual mono setting, but for normal stereo compression, you only have to worry about the left side. The two compressors are called optical (top) and discrete (bottom). The meters in the middle show gain reduction for each. For mastering using this, I'll typically use the optical to get a little bit of gain reduction going, then increase the output to gain stage, then do the same on the discrete compressor. You can fiddle with these to taste as you use your ear, and I also usually sidechain out the low end using the SC Filter on the top right corner and flipping on the sidechain switch just under the left meter. If you do this, where you'll be listening for the change is in your loudest sound in the mid range / high end.
SPL Vitalizer - This unit has multiple functions that you can do, and I'm not even sure exactly what they all do on a technical level. The knob that says "process" is basically your dry/wet knob, so turn it up to hear more of the processed signal. Some of the other knobs are fairly straightforward others are a bit vague, I just tweak them and use my ears to hear the changes.
CamelPhat - I use this plug in as a clipper at the end of my mastering chain with everything off except the MasterMix. I usually don't even use a limiter for mastering, which is maybe a hot take and a lot of you probably want to use limiters, but you really don't have to. I use this for maximum loudness with good transient response, but for a less loud genre such as lo-fi, a limiter may really be better. At the end of the day it's all very subjective and I'm just sharing my process here, you'll certainly come up with your own!
So that's all with the plug-ins! By the way, if you don't have these exact plug ins you can certainly use stock EQ and compression as well, or any plug in you do have. Another thing to note is that while these are the typical plug ins I go to while mastering, I may throw something else on from time to time if I need it and I don't always use all of these, the lesson here is that you can try whatever you think will work and learn as you go! There is no tried and true one-size-fits-all mastering chain, it will vary from song to song and definitely from genre to genre.
Well, there you have it, a little insight on what mastering is and hopefully some information to get you started or get you thinking critically about your own mastering! When I first started, all mastering was to me consisted of slapping an Ozone on at the end and cranking up the maximizer, and you know what we all have to start somewhere. If you want to hear how I use these techniques in my own productions, you can listen to my dance music at Ryahu or my Lo-Fi productions at philip j loaf-eye.
Until Next Time!