Logic Tips - Understanding compression

[Music] I'm Jonah Buchanan and in this video we're going to explore compression what it is how it works and what it does what I've got here is a track which contains four separate instruments but it's only the first one that I'm interested in in order to demonstrate how compression works and that's this drumbeat so before we actually get to see compression compressors in action what we need to do is to find out what they do and why they're used so much in music what compressors do is they change the dynamic range of the sounds that are coming in to them in other words what we can do within a compressor is to change the balancing volume between the quietest moments and the loudest moments of a sound now in a loop like this drum loop it's actually very easy to see the loudest and the quietest moments the waveform really helps us we can see that there are really loud sections here like the biggest moments or the transient hits as we call them within a drum beat but we can also see that as those sounds tale away and we have this decay phase we then get almost silence before the next individual hit happens in other words this loop is incredibly what we call dynamic the difference between loud and soft is completely extreme if you like and what compressors allow us to do is to bring the distance between those quiet and loud moments closer together and actually interestingly the reason why people use compression is because by squeezing those dynamics closer together we actually get more power and energy into a sound let's see how that works now so what I'm going to do is I'm going to open up logics compressor and at the moment I've got one effect on this sound already it's an EQ and we're gonna put the compressor after it so here is logics compressor but what's interesting about the way that compression happens within logic is that actually there are a number of different models of compressor and the one that I'm going to choose today is the classic VTA compressor this one here now what allows me to do to start with is to understand the basics of compression I've got three main controls here this one here called threshold one called ratio and this one here called make up game so moments ago I talked about the difference between the quietest and the loudest moments of an audio file and what we can do with threshold is to set a point between those two places above which we can then start compressing or pulling down the volume of a sound if we imagine this is the quietest moment and this is the loudest threshold somewhere in the middle allows me to say up until this point no dynamic range control is applied and above that point we start making things quieter and then at the last minute we can turn everything back up to take the original volume of the loop back up to where it was and to take the quietest moments with it so that the overall dynamic range is squeezed so let's put the threshold somewhere where we can see what effect it has on a sound I'm gonna put it here at about minus 26 decibels which should leave the quietest moments uncompressed and the loudest moments really squeezed quite hard that's what threshold does the next dial is ratio how hard do I want to make those loudest moments get quieter how much do I want that to happen so the higher the ratio the more I'm pulling down the volume of the loudest bits the bits above the threshold point the smaller the ratio the less extreme that volume squeeze will be so again just so we can understand this let's make a nice high ratio value so we're hearing those transients being pulled down a lot in volume and then lastly we've got this makeup gain control and that's gonna allow me to turn up the volume of the compressed signal remember the way that compression works is that frequencies or volumes above the threshold point are reduced in volume so it stands to reason that actually to start with the whole sound is going to get quieter it's only when I start applying make up gain that I have a chance to turn its volume back up now then one more thing to bear in mind before we actually hear this which is by default logic will turn on what's called Auto gain in other words automatic gain boost we're going to turn that off so we can actually hear the way that compression works without that automatic gain control so here we've got a threshold which is going to pull down the volume of the loudest bits we've got a ratio which is going to ensure that that volume drop is significant and we've turned off make up gain which means that actually this loop should now be not only compressed but much quieter and sure enough it is you can hear that sound sounds much more spanked it's much tighter and it's a harder sort of sound but because it's quieter we're losing quite a lot of the energy from it we're also compressing it really hard so what I'm actually going to do is I'm going to put the threshold up a little bit so less of the sound is being compressed and I'm also going to turn ratio down a little bit we're still going to hear this it's a nice high ratio high enough that we're going to hear the effect but not quite so extreme but now what we're going to do is we're going to boost make up gain back up so we're actually getting all of that compressed signal but at a much higher level okay so now let's compare the uncompressed drumloop with the compressed one here's the original and here's the compressed version now you can hear that there's much more energy a much more sort of attack now in this compressed drum loop and part of the reason for that is because as I said what we've done is to bring the difference between the quietest moments in the loop and the loudest ones closer together now compresses sometimes feature two additional controls what we call attack and release time how quickly the sound responds when it begins to be compressed and how quickly it recovers from compression as the signal drops back below the threshold point now this particular model this classic VCA doesn't feature an attack and release time so what we're going to do is we're going to switch to one of the other ones now so we can begin to see how these additional effects work so let's come in to the studio Fe T model of logics compressor instead now we've got exactly the same settings as before it's retained the settings that I had in the previous example and even though the algorithm at the heart of this compressor will sound slightly different those settings are retained but what I've also now got is an attack in a release time as I said what this allows me to do is to control how quickly the compressor responds as the sound goes up and moves through the threshold points growing in volume which remember is going to happen very quickly because the transients in this loop are so fast the attack time will control how quickly logic begins to compress them similarly as all of those initial transients finish and we get into the decay phase of a sound and the sound drops back through the threshold point the release time will control how quickly the sound goes to its uncompressed form now it might sound like a subtle thing but actually with attack and release times we can make a really big difference to the way that the sound actually behaves so what I'm going to do is I'm going to loop this drum part and we'll actually hear the attack and release times changing again we'll make the threshold and really ratio times announce a little bit more extreme so we can hear this more clearly and then we'll change the attack and release times as we're listening through to see what the effect is [Music] [Music] now that's just the attack time so far but you can hear the difference now when we get to really long attack times the transient actually is finished by the time the compressor is even trying to start work so as a result we get sort of less compression but more volume because the compressor doesn't have time to respond to the signal that's coming into it similarly if the attack time is too short we don't have a chance to hear any of the natural transient before logic is trying to compress that sound and it's trying so hard we actually get this sound which is close bordering on Distortion so a setting around here where we have a chance to hear the initial part of the transient before logic begins to compress it is working really nicely now let's see what happens with release so now we have the mirror image the same effect but in Reverse if the release time is too long the compressor actually doesn't have a chance to return to uncompressed volume before the next transient comes along to send the sound back into compression so we end up with this much more spanked signal the signal which some one way or another doesn't have a chance to go through all of its peaks and troughs again at two shorts a volume we end up with the compressor recovering almost too quickly and it doesn't sound musical anymore so again we're setting a balance between attack and release times that feels musical again let's hear that in and out of context with the track overall it's put in the other instruments and see if we can now find a compression solution for this sound which makes the drums really pop within the mix [Music] so we've now got a much more energized drum part I've kept it really compressed so we can hear that sound very clearly but as a result of working with compression this way and as a result of bringing the balance between the quietest and loudest moments much closer together we end up with this much more inflated exciting drum sound you

Channel: MusicTech

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Keywords: MusicTech, Music Production, MusicTech Magazine, music production for beginners, music production software, Logic Pro x, logic pro, logic studio (software), logic pro x, logic pro tutorial, logic pro compressor tutorial, how to use logic pro compressor, Jono Buchanan, Logic Pro Course, Learn Logic Pro, Understanding compression, Compressor in Logic, Learn Logic Pro X, Logic Step by step, beginners guide to logic pro, how to, tutorial, music production tutorial, Logic tips

Id: UDjkl4W4_Wc

Length: 12min 3sec (723 seconds)

Published: Thu Dec 26 2019