Audio compression - Final Cut Pro Tutorial

- [Jeff] Welcome to Final Cut Pro Ten Weekly. This is Jeff, no Nick, and we're talking about audio compression. Audio compression is basically the idea that you would like to pull back the loudest items and bring up the quietest items, letting somebody who varies how loud and quiet when they speak into a narrower range. When we use a compressor, we're gonna end up pulling back the items that are too loud, and I'm gonna show you how it's gonna make up for that loss of signal strength. I've got a couple of adjustments here that we'll talk about as we work. One of the really cool things about using a compressor means that you have to do a lot less key framing of voices to make them sound even. Important note about monitoring audio. You just can't do it off your MacBook Pro or your iMac speakers. You wanna have studio speakers, such as the M-Audio BX5s or the Mackie MR6s. Those are kind of the minimum of where I'm going, that are $200 speakers, or a set of headphones that have open backs, like the Sennheiser 650s I'm wearing. I wanna give you the warning that noise reduction headphones add quite a bit of hiss. They hide a lot of what's going on, that Earbuds just don't have the dynamic range we need, and frustratingly, when you're in an open office plan, it's really problematic for you to get good audio mixing. You need a room that's got some sort of sound control. So just a quick explanation of this timeline that's out of Final Cut Pro. I've got a version with and without compression on it, and the shot here without compression, I've worked on it earlier, I'm gonna look on the inspector. Want to hide my project, wanna make my inspector tall. This has already had noise reduction done to it, it has a linear phase EQ put on it to help his speech. Generally EQing comes before compression. It has had some noise reduction on it, and I've cut out all the bad moments in his interview and used a flow transition. Something that I wouldn't be as, probably as liberal as I've used here, but I did it here specifically so we could focus in on clean audio. With the clip selected in Final Cut Ten I'm gonna hit x to mark the clip. I'm gonna be using the slash key to play from in to out. - As we got a little bit older, one of the things that happened regularly was Lily got ear infections. - [Jeff] And I'm even gonna go ahead here and say, don't bother showing me any of the video on the timeline. And let's increase the size of this so we can really see the audio, and I'm gonna use the letter z to zoom. I'm just gonna lasso the clip itself, a for the arrow, click on the clip, x to mark the spot. So now the slash key will play through the clip. Optionally, you can go up to the view menu and set the playback to loop, and this allows you to refine, refine, refine. I'm gonna need the compressor effect, and for that I'm gonna go to my effects, I'm in all my audio effects and I'm just gonna type in the word compress. I'm gonna drag this compressor directly to my sound byte. You can see it actually made things louder right away. Let's hide our effects, and with this selected I'm gonna click here to bring up the compressor information. The compressor is gigantic on-screen. I'm gonna go ahead and reduce it to 50% of its size in the top right, so we're able to see and work at the same time. And I'll call out there are a number of presets here, including some for voice, but we're gonna do this all manually. I'm gonna go ahead and play the footage, and turn this on and off just so we can see what the compressor's doing right out of the gate. And we probably could use here our audio meters, so I'm just gonna double-click right here to bring up our meters. Single click, there we go, and we can see what's going on just a little bit easier now. I don't want at this point the inspector height, so I'm just gonna close that back up, just so we have a little bit more space, there we go. All right, now that we're ready to go, let's go ahead and play back this by marking it with the x key and hitting the slash. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. Apparently one of the ways they remedy this is to put tubes into their ears. - [Jeff] You can hear how it's bringing everything up automatically, I wanna show you how this works. So I'm gonna turn it on, and I'm gonna get off the meter and go to the graph mode. This effect works by taking everything above this threshold, in this case it's 20 decibels, and bending it back. It looks like it's set to two, so whatever value it is above 20, it'll get halved, and then it's getting automatically gained up to zero decibels. We're gonna turn off the auto-gain. You see everything dropped. I'm gonna turn the ratio all the way up so everything that's too loud will get pulled back. I'm gonna start with the threshold at zero. With a threshold at zero, nothing's going on. As I begin to roll the threshold over, because the ratio was so harsh, it's going to start pulling back the tops, almost flattening them out completely. So as I drag here, you can see it's bringing back everything, everything, everything. And right now, it's set at minus 20. And I'll play this back and you'll see nothing goes above minus 20, because everything that's above it, it's a 30 to 1 reduction. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. Apparently, one of the ways that -- - [Jeff] So everything above 20 is getting reduced. I'll take it all the way down to 30. Still the same concept. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. Apparently one of the ways they remedy this is to put -- - [Jeff] This here is showing you how much it's kicking in, and this shows you how much it's working on the elements above that level. (man on video continues talking) And this graph part over here is showing you also, its energy, how much it's working to do its compression. This is why we use this rather than the meter to see what's going on. Okay, let's reset everything and take a look what we need to do. First thing I'm gonna do is turn off the auto-gain. This makes up the missing energy that's been robbed by the compression. When we pull things back and then make them up after the fact we gain them back up, we've pulled back the tops, lifted the bottoms, compressing our work. I'm going to set this to zero. I will use the ratio 2.0 is a good spot. You can't really go above three before you get any distortion. And I'm just going to go ahead here and play this. Nothing is being adjusted on our clip right now. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. Apparently one of the ways they remedy this is to put tubes into their ears. - [Jeff] He gets quieter, particularly say, in this section, as things finish because when we speak, we have less air in our lungs and we get quieter at the end of sentences. We'd like our material to average around minus 12. So what we're gonna do is take the loudest moments, so this would be the moments above minus 12, say minus 15 or around minus 20. We're gonna adjust this so it's compressing the elements that are above it. At the very end we'll use a little bit of makeup to pull the bottoms up, hence compression. Pulling down the tops, picking up the bottoms. I'm going to bring back with a two-to-one ratio. Now they're going to be right there about, right, if we're averaging minus 12, we're going to lose stuff. Everything between minus 20 and 12, so we're probably about six decibels too little, but let's play this back and hear it. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. - [Jeff] You can see it's averaging right here, about minus 14, about minus 16 or so. And I'm gonna wanna make up about three decibels. Notice as I do this, everything is much more even. With this off, we've got real highs and real lows in his speech. With this on now, everything is closer together. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. Apparently one of the ways they remedy this is to put tubes into their ear. - [Jeff] On the compression, it's doing exactly what we want, it's evening him out. We have the option, instead of using the makeup here, to just say, hey, get everything to about minus 12, and that's a really good spot for us to work. - [Man On Video] As we got a little bit older, one of the things that happened regularly was Lily got ear infections. Apparently one of the ways they remedy this is to put tube-- - [Jeff] When I approach using a compressor, I'm pulling back the items of speech that are too loud and I'm making it up after the fact. I want my ratio between 1.4 and 3.1, depending on how much they vary. I gotta be careful not to do anything more than distortion, and I'm gonna watch for the compressor to kick in on the graph mode. You have to just be a little bit careful about generalized noise, which is why you want to get clean recordings to begin with, because compression may bring up generalized room noise or spatial noise. And what you might wanna do is do your noise reduction before you get to it or record in a clean environment. Compressors are built for individual voices. Once you've built it, it means that you have to do a lot less key framing to get the voice to sound even. This has been Final Cut Pro Ten Weekly. Thanks for watching.