When to use a limiter instead of a compressor

[Music] all right in today's video we're talking all about the difference between compressors and limiters and we're going to briefly cover what a compressor is and how it works that way you can understand the difference between a compressor and a limiter and we're going to show examples of when it is best to reach for a limiter instead of a compressor and we're also going to dispel the myth that is out there from the old days that a limiter is only supposed to be put on the master bus to gain max volume and trim the peak that is simply untrue there is a bunch of good applications for limiters in your mix when the compressor simply is not cut out for the job there's lots of places where we want to use a limiter instead of a compressor and there's absolutely nothing wrong with that but in order to understand when to reach for a limiter we need to flush it out so you really understand the difference and we're going to show you the difference in action so you can really see it and hear it so let's get right into it all right so the track at the top is the drum bus and in the yellow down below you can see the waveform of the drums as they're playing through now if you could see the crosshairs of the mouse here this big spike is the big spike in volume of the transient of the drums now on the left on the meter you can see the bulk of the drum sound where the big gray blob is is down around -24 DB and these big spikes of the transient or the peak of the Dynamics here where the kick and the snare really crack out these go all the way up to about NE -3 DB so we have this big dynamic range between the loudest Parts where the kick and the snare crack out and the rest of the sound so in order to make the louder stuff quieter and the quieter stuff louder we use Dynamic processing and all compressors are forms of dynamic processing you know manipulating the louds and the quiets to try to gain more of a balance so there's not such a wide range between the super loud stuff and everything else and other Dynamic processors would include limiters dsers noise Gates things like that so we're talking Dynamics processing and we're talking about processing the volume of the waveform and this is why we use compressors so you have less dynamic range and you have things more glued together and it sounds more cohesive and so those big spikes in volume aren't jumping out too far and one of the main reasons you want to do that is so you can get the whole thing a little louder without the tops of these Peaks creeping over the red line and this is precisely why limiters are used on the master bus and they're great for that that's what they were made for and what compressors were made for is controlling the Dynamics of the wave form of everything else other than these giant Peaks the really big Dynamic Peaks are the part of the the waveform that the compressor struggles with the most so they came up with limiters just to manage these Peaks and it can be confusing because a lot of compressors when you're looking at them they're marketed as compressor SL limiter some just say limiter some just say compressor and if you're looking at some of the famous old school ones like the 1176 a lot of times you'll see a company selling an 1176 limiter and another company selling an 1176 compressor so if You' ever been confused by this you're not the only one it is a little convoluted sometimes but these Peaks right here that's the Crux of the problem this is what limiters are for and that's why they were made if your compressor is struggling with these initial Peaks you want to grab a limiter so now before we really flush out the difference between a compressor and a limiter let's talk about the main functions of a compressor here now this is molotto a compressor by TDR Nova and this is really good on a drum bus but it's also just not really designed to handle those big spikes in Dynamics and we're just going to get into the basics today cuz you really only need the basics to understand the difference between a compressor and a limiter all compressors have a threshold an attack a release and a ratio now most of them have some other gadgets on there as well and there's things that are important like the makeup gain and the knee but let's just focus on the four main parameters so first let's talk about the threshold so in order to get gain reduction what a compressor does is it starts to compress the signal of anything that goes beyond the threshold you bring the threshold down until it engages into the signal and the further you bring it down the more of the signal is going to be engaged by the compressor anything that goes above that line starts to get compressed or squashed or pushed back down in terms of volume that's what the threshold is the threshold is that imaginary volume line that you set where anything that goes above it begins to be acted upon by the compressor to bring the Dynamics back down now the ratio of a compressor is basically how hard the compressor is pushing down all of the signal that creeps over the threshold so the higher the ratio the harder it's compressing it back down to the threshold line so a ratio of 1: one is not pushing at all and a ratio of 2: one is very gentle now the max ratio on this molet talk is 10:1 which is pretty strong but that's nothing compared to what a limiter can do a limiter has basically an infinite ratio so anything that goes over the threshold is infinitely pushed back down to the threshold so that's ratio now let's talk about the attack real quick what that's basically saying is the faster the attack time the faster the signal is compressed back down to the threshold after it crosses over that imaginary volume line so the threshold is the imaginary volume line whenever a signal goes over the threshold the attack time tells you how fast the compressor is going to squash it back down to that line and the higher the ratio the harder it's going to push to accomplish that now here's one of the key differences between a compressor and a limiter so all compressors have an attack time even if it's at zero it's still a curve there's still a minute amount of time that it takes to push the signal that crosses the threshold back down to the threshold limiters were created with basically zero or non-existent attack time so it happens so fast that there's no perceptible change and limiters are also designed to push the signal back down to the threshold not only instantaneously but with effectively an infinite ratio so a lot of compressor ratios will go all the way up to 20 to1 and that's where they start to technically consider it like a limiter but a True Modern digital limiter that has no attack time in an infinite ratio is often also called a brick wall limiter we're talking a compressor with one specific function it is to completely squash these Peaks back down to the threshold and it does it as cleanly and as transparently as possible so you might have a compressor that is capable of doing that more or less but it may not sound good it's just not designed to manage these Peaks the way that a limiter is now there's more to that sometimes a compressor can manage these peaks in a way that sounds really cool and they can add a color and a texture to it that is pleasing but a lot of times it's just not really cut out for the job of cleanly and transparently reducing Peak volumes like this so that's what limiters are four so the short answer to when to grab a limiter is whenever you need it in other words if your compressor is just not handling these Peaks the way that you need it to just grab a limiter because that's what it was made for and that's what it does best it's kind of its one and only job and like I said there is nothing wrong with putting a limiter on something like a drum bus limiters are also very useful on pianos cuz posos are very percussive and limiters are used on vocals all the time but here's the thing because the limiter is good at that one function the limiter does not take the place of the compressor it just takes the one job away from the compressor so what you typically see is a limiter used first to manage the Peaks and then you follow it up with your compressor so the compressor can do the rest of the job of the dynamic processing on the rest of the waveform the way that it really does best the way that it's intended to so now let's take a listen into some examples we're going to turn molot talk on and instead of using it to manage the overall dynamics of the drum bus we're going to try to use it the way we would use a limiter and just manage those Peaks so you can hear what happens so with the threshold all the way off the needle's not really reacting to anything and when it engages just a little bit you'll start to see it just reacting to the kick and the snare so now that's how we know that our imaginary threshold line has been brought down from the top far enough to start interacting with these Peaks these Dynamic Peaks here which are the transients of the kick in the snare the way the needle dances you can tell that's what it's reacting to Let's engage it a little further okay we're still only reacting to the kick and the snare you can tell by the needle but now we're reacting to more and more of it and we we have the ratio set as high as it'll go it's at 10:1 so it's really squashing the information as hard as this compressor can the attack is set as fast as it'll go so this compressor is now set up the most like a limiter that this compressor is capable of doing it's acting like a limiter as best as it knows how now let's bypass it so we're going to go back and forth here and listen to what's happening to the kick in the snare with and without the compression do you hear how when the compressors on that we've lost a lot of the snap that we like From The Snare let me turn it off again yeah this compressor is trying to do the job of a limiter but it's making the snare sound like dirt and it's not doing the kick any favors either now that's the molotto now let's take a look at this bus compressor same thing we have the ratio all the way up as high as it'll go at 10: 1 and we have the threshold engaged so we're just getting the Peaks here from the kick and the snare we have the attack as fast as it'll go so this bus compressor is now also trying to do the job of a limiter let's bypass it and listen to the difference so you can hear that this compressor is a little more transparent it's not making the kick and the snare sound as terrible as the molotto was but it's still not doing that great of a job it's still not the sound that I would want if I wanted to get these Peaks under control this really isn't helping the overall feel or the groove of the drum bus now this is the standard stock limiter that comes with Studio 1 so nothing fancy let's go ahead and engage this limiter and see how it compares to those compressors do you hear how much cleaner that is the kick and the snare still sound pretty good they haven't been compromised near as much as the compressors were compromising them that's because that's what this thing is designed to do this thing is only managing the peaks of the kick in the snare and it's not doing everything else we love from a compressor it's not doing the glue and it's not using a slow attack and release to get any kind of GrooVe added to it that's not what it's designed for all this is doing is managing the Peaks but it sounds a lot cleaner and smoother and more transparent than either of those compressors do so that's the key if your compressor is not cutting it just grab a limiter cuz that's what limiters are for and that brings me to things like the 1176 and this is one of those when you see 1176 sometimes it'll say limiter sometimes it'll say compressor and this is a great example to start to explain that gray area between compressors and limiters the 1176 is famous as a compressor because it's so fast so is it technically a modern digital brick wall limiter no but to give you some context of how fast it is the attack time on the molotto at its fastest was .1 milliseconds so super fast right the attack time on the 1176 is not even measured in milliseconds it's measured in micros seconds so it is super super fast so is it technically a limiter H I don't know point being it's not a modern digital brick wall limiter but they can be awesome on drum buses they're also awesome on vocals and on pianos and on all kind of things because they're so fast but it is just like a limiter in the sense that it's just there to manage the Peaks that's what it's best at cuz that's what it was designed for I wanted to show you this and just start to explain that confusing gray area of when does a compressor become a limiter a lot of it has to do with how fast it works and how hard the ratio can slam the signal back down so let's take a listen to this drum bus again without the limiter and we'll try the 1176 on it and compare it to the limiter so here's our drums dry again and we're going to turn on the 1176 now right away you can hear what it's doing to the kick drum it's making the kick have a really nice awesome thump and we weren't getting that from the limiter so this is not as transparent but it is managing the Peaks really well and right now we have the 1176 attack time set at its slowest because that's still super fast and the ratio is at its lowest let's turn it up to its highest now we're at 20 to1 so you can see that the 1176 does a way better job than those other two compressors did because it is more like a limiter so let's compare it to the limiter so what I really wanted to impart with that is not to get hung up on any one tool if you have a compressor that's not cutting it go for a faster compressor and if that's not cutting it just grab a limiter but most importantly if you don't like the sound you're getting for the job that you're doing and managing those Peaks try a different tool and do not hesitate to grab a limiter that's what they were made for and then after the limiter in your effects chain you can still turn on a nice compressor that has great color and character and you can go to work on shaping the rest of that waveform and finishing off the dynamic response and getting it more tight the way you want it getting the groove and the bounce and the glue but you can't accomplish all that with the limiter but you also can't expect to get all of that out of your compressor if it's overreacting to those Peaks a lot of times you'll need a limiter and a compressor after the limiter and there's nothing wrong with that and there's nothing wrong with using modern digital brick wall limiters in a dah whether it's a drum bus a piano vocal basically wherever you need it if you're managing Peaks that are just too much for a compressor without making them sound terrible then grab a limiter because even a really nice compressors may not just be cut out for that job because that's not really what they're designed to do that's what limiters are designed to do so there you go I hope that helps do not hesitate to grab a limiter and don't let anyone tell you that you're not supposed to put a limiter on whatever you need to put it on because if you need it you need it and you got to remember a lot of recordings are just not that great sometimes you have things jump out and if it's only one or two things jumping out sure some volume automation might do it for you but if you have a really Dynamic drum bus or a really Dynamic piano performance or even a really Dynamic vocal performance use a limiter to just manage the Peaks because it does it transparently and cleanly without butchering the Peaks and then you can go to work with the compressor and not have to overwork your compressor and use the compressor more for what it was designed to do and before we leave this I also want to explain that there are more ways than just using a limiter to manage those Peaks there's also Clippers and Clippers are really cool too now as I said with the limiter anything that goes over the threshold gets squashed back down a Clipper doesn't squish it back down a Clipper literally trims it off like scissors on a haircut and that can have a really cool effect too and if you haven't checked out my video called saturating transients I basically do licate the job of a Clipper but with a free saturator and it's more or less doing the same thing but it has a slightly different effect where you get even more harmonics introduced into the waveform than you would with a Clipper so there is more than one way to go about managing those Peaks but if you want a clean transparent tool to manage those Peaks grab a limiter that's what they're for and in the next video we'll get further into those parameters on the compressor the threshold the ratio the attack of the release and we'll break that down in more detail and then after that I'll get a video out showing the 1176 la2a combo because if you've never seen that in action it's really cool but there it is that's the difference between a compressor and a limiter and when you should reach for one and not the other and I had some comments asking me to explain this so I hope that helps and I hope that answers all your questions let me know what you think in the comments and stay tuned for those next videos on the compression topics and I'll catch you on the next one [Music]

Channel: Audio Mountain

Views: 8,941

Keywords: audio engineering, mixing, music, guitar, drums, EQ, compression, saturation, mastering, DAW, tutorial, spectrum analyzer, equalization, dynamics, recording, recording studio, microphone, how to, waveform, transient, sidechain

Id: AKFemR5HkLI

Length: 20min 10sec (1210 seconds)

Published: Fri Dec 29 2023