To listen music critically does not equal to listen for pleasure. It’s kind of the opposite of sitting back and enjoying music without much thinking about what you hear. What is it for? It’s to be able to detect what’s going on, so you can do all those things later, to your own music. Whether it’s recording, mixing or mastering, you’re going to run into this part of the creative process, sooner or later. That’s why it’s pretty important to train yourself and your ears. So ultimately you can reach a point where you are able to listen like a pro. You can tell what you hear only if you’ve already heard something like that before. It’s easier if you’ve experimented with sounds and music yourself before you get into this shit.
Listen critically – for these aspects
Yeah, so there are a couple things to listen for. But before we get lost in the depths of this crap, one more thing to note. You need a good set of monitors. I don’t care if it’s small, medium or big speakers or headphones. There are only two aspects about them that really matters. One is that they can reproduce the whole audible frequency spectrum fairly well. The other one is that make sure you’re used to them already. So on to the aspects to listen for.
Width and panning
The stuff about whether you can hear the instruments coming at you in a wide area, a narrow area, or just a single point. Also the exact direction where they’re coming from (left, right, center and anything in between). Listen for these things, and note ’em down, even mentally. Like for example “kick drum – center, bass – center, hi-hat, slightly to the right, rhythm guitar – hard left”. Shit like that.
Listen for how big of a frequency range the instruments occupy. It’s entirely possible that in some mixes, the bass will be nothing more than a wooly, muddy bog of a sound. In other ones, it might have both depth and a biting, hi-fi high end. Listen for these and don’t crap yourself too hard if out of the fog of that sugary slime of music they do appear. Suddenly.
Dynamics (or the lack of them) – compression
Yeah, if the sounds are coming out flat and sort of small, you know they have a limited dynamics range. But at the same time, they also appear louder. Is it a good or a bad thing? It’s neither. It all depends on what they do and what they achieve. Both in your emotionally, and aesthetically in the whole mix. So compression can be a friend and a foe, too. Usually not at the same time. Distortion can cause compression too, though interestingly, it doesn’t render a sound flat and small in an obvious way like pure (over)compression does. Knowing that, you can use both at the same time to cure the side effects of both, while keeping the good aspects about them. If you know what to listen for!
Depth and distance – level & ambience
It’s the perceived distance of the sounds/instruments from you as a listener. If you can tell whether a sounds is in your face or far away, you’re on the right track. The next thing to listen for is whether it’s a reverb, a delay or something else that moves that track in the back of the mix. Or level and equalization. Because softer, quieter sounds appear further in the back. Even without using any reverb or delay. And if you chop off the lows and highs, you can simulate distance, too, while remaining dry at the same time. But speaking of reverb and delays, besides creating depth, they also fill spaces. You know, the empty, softer gaps between sounds. It’s a cool and often overlooked feature of them. Listen for this, too! Sometimes, it’s not an additional ambience effect that adds the reverberation to the sounds. It can be the way they were recorded as well. It can be a couple of metal sheets around the drum kit, or a wooden room, and the sound is already full with reflections and high end. Having a room mic at where the guitar amp was recording will give you a nice 3D sound as well, without having to use additional reverbs. It’s not always easy to tell a room reverb and a real room apart, but that’s not the point of critical listening either. You can this poor cat in many different ways. It’s the end results that matter.
Some sounds cannot be achieved without using effects. Some of these are electronic ones, like the usual ambience, modulation, pitch or saturation/distortion effects. But there can be acoustically created effects in a mix as well. Not only the above mentioned room sound modifying ones, but all kinds of other, DIY effects as well. Think of a purple gorilla grinding his genitals against the guitar strings in a highly periodic manner. Got it?
Very important. Are the sounds remain pretty much static all the way through? Or do they move in the stereo field? Do their levels change during the song? Do their frequency content change? Do their dynamics and ambience change? All the above things we went through can change, even constantly. Listen for these, and take mental notes.
The instruments themselves
Yup. Because it’s important, too. Can you tell if the singer’s a boy or a girl? A DI or miked acoustic guitar? A real drum kit or a drum machine? A Strat or a Les Paul? A fretted or a fretless bass?
The best way to practice the above is to ask yourself questions about the music you’re listening to. If you can answer your own questions, it’s good. If you can’t, go back to that part and pay attention to it harder. You’ll get the hang of it, eventually.