7 ways to reduce noise in sound recordings (Part 1)

hi everyone in this two-part video we're going to be taking a look at ways of effectively reducing noise or cleaning up audio recordings in Pro Tools or with Pro Tools in association with some of the software in this first part we'll be looking at problems including rumble hum static or crackle and finally broadband noise in part 2 we'll be tackling a variety of other issues including clips audio excessive reverb in recordings and finally audio with a variety of different issues you can see in this particular session I've got a whole multitude of things open at the moment these are some of the plugins which I'm going to be using in this tutorial let me just close those for a second and you can see on this track at the top I've got various different problematic pieces of audio so my goal in this video is to try and tackle each of these with a variety of different tools I might just create a duplicate playlist on here actually so we can a be between the two let's call this cleaned up when you create an alternate playlist or a duplicate playlist by the way you can now toggle between them very easily holding down the shift key and the up and down arrows and if you look carefully here you see if I press shift and up and down arrow then it will switch between those playlists so in the case of what we're doing here that's a good way to just do an a/b comparison let's take a listen to the first piece of audio which as you can see is labeled low Rumble here we go accenture is a global professional services company and provides strategy consulting technology and operation services James Hallam it's MD of the fuels resale practice covering Europe Africa and Latin America ok so that's pretty obvious it's got a very considerable Rumble on there now I've put this one first because this is actually the easiest one to deal with let's just take a look in fact if I just show you the waveform in a little bit more detail it's quite clear from that that there is something going on and zooming in you can see that there's some low frequency noise so let's just try and tackle this this is very simple because it is exclusively in the low frequency domain we don't seem to have much problem with higher frequencies so the simplest form of you can apply all the most effective tool in this case could be just a one band EQ and you know it's easy to overlook the usefulness of a plug-in like this so let's just play this and see what we can do what we probably want to do is just do a high-pass filter that's going to cut everything below certain frequency the default setting is going to be extremely thin far too thin so I'm just going to drop the frequency let's say we'll start at 100 Hertz I think okay and then just play this again accenture is a global professional services company and provides strategy consulting now there is still some stuff coming through and that's probably because although most of this noise I would imagine is below 100 Hertz it's the steepness of the curve so that's adjustable here and you can see that it goes up in 6 DB increments sometimes this is referred to as the curve order so for example 6 decibels per octave would be a first-order curve 12 a second-order 18 third order 24 fourth order so I'm actually going to try and apply that 24 decibels per octave roll-off just so that it tails off a lot more quickly with regards to the frequency that you set in a high-pass filter whatever you set here doesn't really set the absolute start point for the roll-off this is actually the minus 3 DB point so in other words at 100 Hertz it's already tailed off by about 3 decibels anyway let's take a listen to this Accenture is a global professional services company and provides strategy consulting technology and operation services it's reasonable I think I might even go a bit higher let's take this up to yeah maybe the 118 and a bit Accenture is a global professional services company and provides strategy consulting technology and operation services try even higher it's always a balance with this kind of thing you know I could of course go really high and filter out everything but you're going to start to eat into the dialogue quite quickly there so I wouldn't go above I don't know 150 maybe with this Accenture is a global professional services company and provides strategy concise fine the only like consideration with this is that if I just keep that on there it will filter it it's gonna affect anything else on the track and once I could automate it sometimes you want the waveform to update as well and the thing about applying any kind of plugins in real time whether the DSP or native is that it does not affect the waveform so what I might actually do here is copy these settings then I'm going to apply this but as an audio suite plug-in so I'm just going to open the exact same one here you know the more plugins you have the bigger this list is going to be and it just gets crazy after a while so sometimes you might want to filter them by manufacturer it's easy to find stuff there's the one band EQ I've copied those settings so I could click here and then paste the settings I mean they were very simple anyway but you can imagine on a more complex plug-in that's a very useful feature now preview this just to make sure it sounds fine and I now when I render it the way for my update which is a an easy visual indication of what we've done let's just a B between the two so I'm going to use the shift and/or pyro shortcuts of switch playlists here's what we had accenture is a global professional services company and provides strategy consulting need to get rid of this to truly hear it so let's drop that plug-in because our still filtering it now let's hear it Accenture is a global professional services company and provides strategy consulting technology and operation services and then the cleaned-up version Accenture is a global professional services company and provides strategy consulting technology and operation services ok that was quite effective now we're going to move on to reducing hum and in this case we've got this file which is labeled horrendous hum because lo and behold it's got horrendous 4minute areas 99% of our work is Volkswagen because that's where the big market is but we do in this case a simple high-pass filter won't really cut it because as well as that low frequency we've also got harmonics and multiples of the fundamental frequency and one plug-in which I like to use for this kind of stuff is from Mac DSP and it's called the N F 575 noise filter and this allows you to apply a series of very narrow notches narrower than you can in most normally queues in order to filter things such as this so this piece of audio was recorded in the UK and I would hazard a guess that the fundamental frequency is probably 50 Hertz so the way that I like to use this plug-in is I'll use one of the buns let's use this one and I'll reduce the range to the minimum which is 40 DB cut now with a bun soloed we're only going to hear what will be taken out let's just take a listen and what you really want to do is sweep the frequency until you hear the hum the loudest well okay that's quite prominent I would recommend watching this video by the way either through headphones or decent quality monitors because there's some low frequencies that we're going to be dealing with here so 50 Hertz that's no surprise because this audio is recorded here in the UK where the mains frequency is 50 Hertz we can also reduce the bandwidth or the cube to the minimum because we don't want to affect any surrounding frequencies or necessarily let's just compare between having that active and not active so turn it off first 99% of our work is Volkswagen now with that first cut applied 99% of our work is Volkswagen okay so that's reduced that very lowest frequency what we now need to do is move on to the harmonics and quite often they will be direct multiples of the fundamental so let's just see if that's the case I'm going to go on to the next band do the maximum amount of cuts and then sweep around around 100 Hertz [Music] yeah so you see us I'm going through hundred Hertz there it sounds the worst let's reduce the bandwidth okay and take your listen to that so what you're hearing there is what we're going to take out now let's compare this so see what we've got 99% of our work is Volkswagen because that's where the big market is that's get in there next frequency I'm just going to guess here that it's probably 150 Hertz for the sake of speed in the video we'll cut that 99% of our work is Volkswagen because that's where the big mark now there's a little bit of something higher up perhaps it's two hundred ninety nine percent of our work is Volkswagen because that's where the big muscle little bit harder to tell here but let's just try it and reduce this to the maximum or the minimum depend on which way you want to look at it and play that 99% of our work is Volkswagen because that's where the big market is compare that with without the plugin 99% of our work is Volkswagen because that's where the big muff there is one slightly weird thing with this plug-in which always seems to happen which is when you first play it it takes a fraction of a second before it to actually kick in take a listen when I run this you'll hear the noise and then it will rapidly tail off knowing T on here that there's like a low frequency kind of thing going on knowing to yongsik I'm going to do the same trick here copy the settings open the audio suite version of it and apply it there once again let's have a look at this by manufacturer just because it's a lot easier to find it and f5 7/5 paste the settings here there we go now I can render it ok a notable difference in the waveform let's just keep this open in case I need to change anything just make it inactive for now here we go so the noisy version 99% of our work is Volkswagen because that's where the big market is and then the new version 99% about once again there's a strange thing at the beginning knowing too young in this case it doesn't actually matter because I could just do something like that and you can see that there is actually still some stuff going on there a little bit 99% of our work is Volkswagen because that's where the big market is but it's a lot better sometimes you can apply it twice actually you know if you're running it in real time these give you only 40 DB of reduction which is quite a lot but you can actually apply two of them and then that effectively gives you twice the gain reduction on any given band anyway we've applied audiosuite processing and it's it's reasonable so now let's move on to reducing static and here we've got a clip which I've had to mock this one up because I didn't really have anything with a sufficiently bad static but this is how it sounds I think it's a real it's a real mix and we have certain countries like Norway where I think it's last year 23% of all new vehicles were electric now you're unlikely to find that kind of thing on a modern recording not to that extent anyway but if you were ever remastering vinyl or remastering some vintage recordings then you may find the static can be quite a problem let's take a look at a plug-in for this and this time we're going to use one from Sonics which is the Sonics D clicker now without going into too much detail about all of the settings on this basically it breaks the noise down into three categories pop click and crackle sounds like a breakfast cereal but in essence pop is the slightly longer duration kind of artifact clicks are shorter and crackle is very short and generally rapidly repeated I don't think we're going to have any problem with pop let's just try the default settings to begin with I suspect it's going to start to adversely affect the audio because of this I might need to turn that band off or take a listen I think it's a real it's a real mix we have certain countries like Norway where I think it was last year 23% of all new vehicles were electric yeah something weirds going on so what you can do with this is you can listen to only the audio that you're actually taking out so the moment I listen to the original listen to you diff and that's the difference so what you want to try and do here is not hear any dialogue more minimal minimal dialogue and I can hear some and I suspect is this turn off okay that's helped let's just see how that sounds she knows really how fast will increase I think it's the real it's reasonably well not good enough so let's go back here and I'm gonna change the threshold a little bit see if I bring it all the way down that starts to really eat into the dialogue out see it will increase the question is really so it's a question of balance here maybe that I could increase the sensitivity a little bit let's try that so for me electrification is a reality it will increase the question is really how okay now let's try changing a few settings in the G clip section so I'm just gonna run it once again I think it's the real it's a real let's see what I can get away with with this pull it all the way down of course you can hear dialogue here so take it up a bit maybe that this I think it's a real it's a real mix and we have certain countries like Norway where I think it's last year 22 percent of all new vehicles were electric but then there are certainly other countries where that's in a much much smaller percentage so for me electrification is a reality it will increase the question is really okay it's not perfect but just for speed in this video let's say that it's good enough for now I'll render it you know if you have plenty of time of course you could spend ages getting that perfect let's just do a quick comparison between those two once again I think it's a real it's a real mix and we have certain countries like Norway and they're not versioning is last year 23% of all new vehicles were electric then there are certainly other countries where that's you know a much much smaller percentage so for me electrification is in reality that's not a bad result given how severe it was now we'll move on to broadband noise reduction so broadband noise is noise which occupies a wide frequency range such as the sound of a computer farm or an air conditioning unit let's take a listen to an example of something like that here I like its performance it's quick and it's comfortable like the autopilot because when the traffic is really congested you can you still have to concentrate but you can't concentrate slightly less okay this was recorded outside and the background noise in this case is the sound of a road that's not too far away from where the interview is taking place and there are there's probably another issue in here really there's also a low frequency sound that we could probably do with just removing so before I even start to look at the actual broadband noise reduction I might as well just apply it apply a high-pass filter maybe at 100 Hertz because there's no point in that even being there I'll just get rid of that so that's stage one already quite a change in the waveform but now let's move on to the reduction of the noise itself and there are many tools which you could use for doing this and sometimes you know one might be better than the other another time it might be a different one that's preferable so you've really got to kind of try whichever tools you have at your disposal in this case I'm gonna try the isotope rx-7 voice d noise now this is available in the full version of rx and it's also available as an audio suite plug-in here in Pro Tools and if you're up against the clock with a deadline and you have quite a lot of problematic or do to deal with quite often adaptive mode actually gives you a very good result that's basically an automatic mode let's just see how this sounds straight off I like its performance it's quick and it's comfortable like the autopilot because when the traffic's really congested you can bypass it still have to concentrate but you can't concentrate slightly less it takes over some of the driving that's not too bad if you want to go in and do it manually then what you need to do is find a section of noise on its own with no dialogue in it so it's either going to be there or there let's just see which one might be best for some of the driving I like the fact that one's got a breath in it also I'm probably gonna use this - that little lip smack at the end or possibly that that will do it at the end there okay so now I need to turn off adaptive mode click on learn and because we're doing this as an audio suite plug-in rather than something in real time I'm just gonna click on this little preview button and now you can see that's created what you call a noise profile so that's the overall contour of what this plug-in considers the noise to be now that it knows that I can listen to the whole file and hopefully the noise reduction is reasonably effective we probably will need to change the threshold and the reduction you don't really want to eradicate the noise 100% because on something like this you know this interview would be in this case seen on camera and you can see that he's outside so it would be very strange in the actual video where this already who came from for him to be talking in complete sonic isolation you want to keep some semblance of the background sound in there because it helps to put him in that location but nevertheless we want to reduce it so it's about reduction rather than complete eradication so let's preview this like it's performance it's quick and it's comfortable like the auto if I try and do this when the traffic's really congested you can you still have to concentrate that you can't concentrate slightly less here that's really affecting the dialogue now let's try and do I don't know 10 or 11 DB of gain reduction like its performance it's quick and it's comfortable like the autopilot because when the traffic's really congested you can you still have to concentrate but you can't concentrate slightly less it takes over some of the driving I like the fact that it okay that's not bad I'm doing these quite quickly and you know sometimes you do have to do that so although it would be nice to always go in and tweak the settings and get it perfect and spend ages messing around with it the reality is with you know a lot of jobs you simply don't have the time to do that so sometimes it's a balance between time and deadlines let's just do a quick a/b comparison between these so once again I'm using the shift and up and down arrow shortcuts here to toggle between the playlists so let's start this running is a noisy version I like it's performance it's quick and it's comfortable it cleaned up the autopilot because when the traffic's really congested back to the noise you are still have to concentrate that you can't concentrate slightly less as it takes over some of the driver and the cleaned up I like the fact that it isn't missing any carbon dioxide this isn't costing you anything for fuel there are some artifacts in there but nevertheless it's a reasonable result that's it for part one in the next video we'll be looking at ways to effectively reduce clipping excessive reverb and we'll also be tackling an old recording from cassette which has a variety of noise issues I'll see you there you [Music]

Channel: Paul Maunder

Views: 12,365

Rating: 4.976048 out of 5

Keywords: Paul Maunder, Pro Tools, Tutorial, Ultimate, Avid, Izotope RX, Sonnox, De-Clicker, Noise Reduction, Remastering, Digital Remaster, Clean Up

Id: 4enzsVu0vko

Length: 20min 9sec (1209 seconds)

Published: Tue Jul 23 2019