Audio Editing - Noise Reduction Filters Video

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Audio Editing - Noise Reduction Filters

Let's open a couple of more examples. Again, navigate to your Media Resources folder, we are going to choose Tony Noisy.mov and Vinyl. Let's start with Tony Noisy, Soundbooth features some incredibly effective tools for automatically cleaning up audio with undesirable noise and defects. These tools make quick work of most common clean up jobs. There are a few limitations to their use however and they need to be considered before choosing the appropriate path to take. While they can be used to varying degrees of success for any instance of undesirable noise, they are vastly more effective for noise that remains fairly constant throughout the file or selected region. Let's remove some noise. We have here a clip of our old friend Tony, doing his interview but this time it seems that someone in the studio forgot to turn off the fan used to cool the room in between takes. It's sad, because the director really likes how Tony did this particular take and wants to know if there is any way to get rid of that fan noise. We have two things working in our favor here. The noise is constant throughout the entire clip as you can clearly see here in the Spectral View and there is a good section recorded audio which contains nothing but the noise itself which is right here. Let's take a listen to this whole clip so we can hear what I am talking about. This region here that has no signal other than the background noise allows Soundbooth to take a snapshot of the frequency content of the noise. So it can be more effective in removing it when the speaker actually begins talking. To take the snapshot, we select the region of audio which contains only the noise using the Time Selection Tool. Go ahead and open up Clean Up Audio in the Tasks panel and click Capture Noise Print. Now it's time to actually get rid of the noise. You can either select the entire file or simply deselect. Go ahead and click the Noise button. That brings up a little dialog box here, that gives us all of our Noise Reduction settings. Since we have an effective noise print, make sure that the Use Captured Noise Print box is checked. The Reduction and Reduce By sliders are the settings that actually tell the noise reduction process how to behave. The Reduction slider sets how much of the signal Soundbooth perceives as noise and how much of the signal Soundbooth perceives as good stuff that it wants to keep. If you find yourself removing portions of signal that you don't want to get rid of, turn down the Reduction slider a little bit. the Reduce By slider determines how much the signal that Soundbooth believes is noise gets turned down. You can click your Preview button then listen to the effects that these settings are having in real time. That's what we will do here. Let's click Preview and play with the sliders a little bit. You can hear a little bit of artifacting going on in the background. This is an unfortunate side effect of the noise reduction process. When you are reducing noise, your goal is typically going to be to reduce the noise as much as possible while not introducing many artifacts to the sound you want to keep. I find that setting of the Reduction slider quite high to Aggressive and turning the Reduce By slider down a little bit tends to be the happiest medium. Let's tweak the sliders a tiny bit more and really find that magical spot. There is still a little bit of artifacting there, but I figure we can probably get away with it, especially if there is little background music going on. Once you have gotten your settings the way you want them, go ahead and press the OK button to finally process the audio. You can see the dramatic effect that the noise reduction has had on the background noise in the clip. If you ever want to go back to your pre-processed state you can do so right down here from the History Panel. Let's go ahead and just play the section with Tony actually speaking, so you can hear the final effect. You notice that you can still hear some of the fan in the background. But this is probably the best that we are going to get it. If you have the option in these kind of situations to use and alternate take without the noise in the background, it's typically a better idea to do that. But in a case where you are stuck, using a clip with the noise, the noise reduction filters can be a great help to you. Next, I want to take a look at the Clicks & Pops and Rumble reduction. To take a look at that I am going to come up here and change our clip to Vinyl. These filters in Soundbooth are specifically designed to remove artifacts that you might find if you are taking your old Vinyl records and transferring them to digital media. Let's take a listen to the sounds we have got here. You can clearly hear the two different types of noise that we have introduced here from the vinyl. There is a good deal of rumble down at the bottom and machine noise and right here you can see the clicks and the Pops from the dust that's left on the record. Let's remove clicks and pops first. Just come right over here and click the Clicks & Pops button. Since this is such a common type of noise that people try to get rid of, Soundbooth doesn't require a noise print for this, as it actually has a noise print built into the system. Again, we can preview our effect live while we are working with the slider. Let's take a listen to what it does. The small interruptions in the sound that you hear when we put the slider up towards the top is simply the process we are having a little bit of trouble keeping up. Once the OK button is pressed, those interruptions will not be present in your final audio. So I am just going to go ahead and finally set the slider all the way up to a 100. We will hit OK and after it processes, we will be able to see and hear the changes made. You can already see those clicks going away pretty significantly. Let's take a listen to the processed audio. You can also get rid of some of that low end rumble. Go ahead and click your Rumble button. The Rumble filter is pretty much just a high pass filter. It allows you to set a threshold here, anywhere between 10 and 80 hertz and it simply cuts all of the frequencies below that threshold. Let's click the OK button and see what we get. You can see down here this small, black space that's appeared which shows us that a lot of that low end rumble is gone. Let's take a listen. You can still hear a lot of noise in the background, but the lowest bit of that rumble, all the stuff under 80 hertz is completely gone. I would like to try to remove some of the rest of that noise as well though. But the problem is that we don't have any region in this file from which we can capture a noise print. Soundbooth does allow you to eliminate noise without a noise print. It's an alternative method and it doesn't work as well as if you do have a noise print. But if you find yourself in a situation such as this, you can go ahead and give it a try. Let's see what happens. Go ahead and click the Noise button. You will notice this time that Use Captured Noise Print is actually grayed out, because Soundbooth realizes that we don't have a noise print captured yet for this particular clip. Your Reduction and Reduce By settings are going to be a lot more important this time because there is no noise print for Soundbooth to work with. Let's click the Preview button and see what kind of results we can get. Now that's kind of a cool little Flange effect there, isn't it? You typically have to be much less aggressive with your settings when you don't have a noise print to work with. Let's continue to tweak a little bit. You can hear the artifact dramatically increased when you pull the Reduce By slider up. Those settings sound pretty good. Let's apply the effect. You can see by the results within the spectrum that Soundbooth does a pretty good job of removing the noise even without a print. Again, your results are never going to be perfect especially when you are working without a noise print. But you can tell that our audio has been drastically cleaned. Let's take a listen. In the next lesson, we are going to see how to make manual edits within the Spectral A

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Let's open a couple of more examples. Again, navigate to your Media Resources folder, we are going to choose Tony Noisy.mov and Vinyl. Let's start with Tony Noisy, Soundbooth features some incredibly effective tools for automatically cleaning up audio with undesirable noise and defects. These tools make quick work of most common clean up jobs. There are a few limitations to their use however and they need to be considered before choosing the appropriate path to take. While they can be used to varying degrees of success for any instance of undesirable noise, they are vastly more effective for noise that remains fairly constant throughout the file or selected region.

Let's remove some noise. We have here a clip of our old friend Tony, doing his interview but this time it seems that someone in the studio forgot to turn off the fan used to cool the room in between takes. It's sad, because the director really likes how Tony did this particular take and wants to know if there is any way to get rid of that fan noise.

We have two things working in our favor here. The noise is constant throughout the entire clip as you can clearly see here in the Spectral View and there is a good section recorded audio which contains nothing but the noise itself which is right here. Let's take a listen to this whole clip so we can hear what I am talking about.

This region here that has no signal other than the background noise allows Soundbooth to take a snapshot of the frequency content of the noise. So it can be more effective in removing it when the speaker actually begins talking. To take the snapshot, we select the region of audio which contains only the noise using the Time Selection Tool. Go ahead and open up Clean Up Audio in the Tasks panel and click Capture Noise Print.

Now it's time to actually get rid of the noise. You can either select the entire file or simply deselect. Go ahead and click the Noise button. That brings up a little dialog box here, that gives us all of our Noise Reduction settings. Since we have an effective noise print, make sure that the Use Captured Noise Print box is checked. The Reduction and Reduce By sliders are the settings that actually tell the noise reduction process how to behave.

The Reduction slider sets how much of the signal Soundbooth perceives as noise and how much of the signal Soundbooth perceives as good stuff that it wants to keep. If you find yourself removing portions of signal that you don't want to get rid of, turn down the Reduction slider a little bit. the Reduce By slider determines how much the signal that Soundbooth believes is noise gets turned down.

You can click your Preview button then listen to the effects that these settings are having in real time. That's what we will do here. Let's click Preview and play with the sliders a little bit.

You can hear a little bit of artifacting going on in the background. This is an unfortunate side effect of the noise reduction process. When you are reducing noise, your goal is typically going to be to reduce the noise as much as possible while not introducing many artifacts to the sound you want to keep. I find that setting of the Reduction slider quite high to Aggressive and turning the Reduce By slider down a little bit tends to be the happiest medium. Let's tweak the sliders a tiny bit more and really find that magical spot.

There is still a little bit of artifacting there, but I figure we can probably get away with it, especially if there is little background music going on. Once you have gotten your settings the way you want them, go ahead and press the OK button to finally process the audio. You can see the dramatic effect that the noise reduction has had on the background noise in the clip. If you ever want to go back to your pre-processed state you can do so right down here from the History Panel. Let's go ahead and just play the section with Tony actually speaking, so you can hear the final effect.

You notice that you can still hear some of the fan in the background. But this is probably the best that we are going to get it. If you have the option in these kind of situations to use and alternate take without the noise in the background, it's typically a better idea to do that. But in a case where you are stuck, using a clip with the noise, the noise reduction filters can be a great help to you. Next, I want to take a look at the Clicks & Pops and Rumble reduction.

To take a look at that I am going to come up here and change our clip to Vinyl. These filters in Soundbooth are specifically designed to remove artifacts that you might find if you are taking your old Vinyl records and transferring them to digital media. Let's take a listen to the sounds we have got here.

You can clearly hear the two different types of noise that we have introduced here from the vinyl. There is a good deal of rumble down at the bottom and machine noise and right here you can see the clicks and the Pops from the dust that's left on the record. Let's remove clicks and pops first. Just come right over here and click the Clicks & Pops button. Since this is such a common type of noise that people try to get rid of, Soundbooth doesn't require a noise print for this, as it actually has a noise print built into the system.

Again, we can preview our effect live while we are working with the slider. Let's take a listen to what it does.

The small interruptions in the sound that you hear when we put the slider up towards the top is simply the process we are having a little bit of trouble keeping up. Once the OK button is pressed, those interruptions will not be present in your final audio. So I am just going to go ahead and finally set the slider all the way up to a 100. We will hit OK and after it processes, we will be able to see and hear the changes made. You can already see those clicks going away pretty significantly. Let's take a listen to the processed audio.

You can also get rid of some of that low end rumble. Go ahead and click your Rumble button. The Rumble filter is pretty much just a high pass filter. It allows you to set a threshold here, anywhere between 10 and 80 hertz and it simply cuts all of the frequencies below that threshold. Let's click the OK button and see what we get. You can see down here this small, black space that's appeared which shows us that a lot of that low end rumble is gone. Let's take a listen.

You can still hear a lot of noise in the background, but the lowest bit of that rumble, all the stuff under 80 hertz is completely gone. I would like to try to remove some of the rest of that noise as well though. But the problem is that we don't have any region in this file from which we can capture a noise print. Soundbooth does allow you to eliminate noise without a noise print. It's an alternative method and it doesn't work as well as if you do have a noise print. But if you find yourself in a situation such as this, you can go ahead and give it a try.

Let's see what happens. Go ahead and click the Noise button. You will notice this time that Use Captured Noise Print is actually grayed out, because Soundbooth realizes that we don't have a noise print captured yet for this particular clip. Your Reduction and Reduce By settings are going to be a lot more important this time because there is no noise print for Soundbooth to work with. Let's click the Preview button and see what kind of results we can get.

Now that's kind of a cool little Flange effect there, isn't it?

You typically have to be much less aggressive with your settings when you don't have a noise print to work with. Let's continue to tweak a little bit.

You can hear the artifact dramatically increased when you pull the Reduce By slider up.

Those settings sound pretty good. Let's apply the effect. You can see by the results within the spectrum that Soundbooth does a pretty good job of removing the noise even without a print. Again, your results are never going to be perfect especially when you are working without a noise print. But you can tell that our audio has been drastically cleaned. Let's take a listen.

In the next lesson, we are going to see how to make manual edits within the Spectral A

Transcription by: Scribe4you Transcription Services