My actor yelled a line, and I think the fact the boom was so close and the environment was a confined interior caused pretty poor distorted audio. I obviously should have done it outside or made sure the boom wasn't so close... something, because it sounds like he's blowing the mic or something. I turned down the levels so the levels themselves are not clipping, but something definitely went wrong. Any idea of any filters or anything that could potentially make it sound better? I realize this is a little hopeless, but my actor is being a prick and won't re-record despite being paid a fair amount so I'm just trying to find an alternative. Thanks.

Take a look at the raw waveform, before you adjust the levels.

If the levels go all the way to the top, (and tend to stay there during the distored passage) then you have a serious problem.

Sony's Noise Reduction 2.0 has some tools such as Clipped Audio Restoration. This can help in certain cases, but not all. This tool can be used in Sound Forge or Sony Vegas.

Is the actor available to re-record the line?

Sony's Noise Reduction 2.0 is very good. I was suprised to recently learn that it is now included in the price of Sound Forge.

Send me a private email and I will respond tomorrow.

I'm facing similiar problems (with a band being recorded) and the audio is completley distorted at the loud parts. Desperately need some way to "fix" the audio in post. I will try out the Sony Noise Reduction if I can get my hands on it. Any other suggestions?

There is no software fix for distorted audio. An occasional clipped peak may be improved, but if your audio is 'completly distorted' you really only have two options. Live with it or replace it.

Tell your actor you'll get someone else to revoice the line with the video of him doing it, that should get him to come around.

There is no software fix for distorted audio. An occasional clipped peak may be improved, but if your audio is 'completly distorted' you really only have two options. Live with it or replace it.That's right. Clipped audio is like a painting or picture where half of it was cut off. No algorithm can reproduce the missing piece from the information that is still left. If you look at clipped audio in a waveform editor, you'll see the analogy.

- Martin

...
Sony's Noise Reduction 2.0 is very good. I was suprised to recently learn that it is now included in the price of Sound Forge.
....

Sound Forge 9 gives you a whale of a bang for the buck, especially now that they've included both the full Noise Reduction 2.0 AND the Izotope Mastering tools in the base price. NR by itself is almost the same price as the full SF package. That's a lot of value!

Well, of course there is no way to completley fix distorted audio, but I'm interested in the part where you mentioned improving the occasional clipped audio.

As others have noted, this is certainly a bummer situation, as is always the case with severe distortion in important audio.

Audio noise is not the same thing as audio distortion, and there are a number of applications that can help reduce or eliminate audio noise. But in terms of distorted audio, it is rarely worth the effort as there is really no way to make it sound NOT distorted. The best that can be hoped for is to shave away some of the frequencies that comprise the distortion to perhaps make it less instusive...but its still gonna sound like distorted audio.

-Jon

Will, can you post a short clip up? (Even mp3 would be fine.)

One of our camera operators, while filming an important live action scene, set the levels wrong and did not monitor his audio.

About 50% of the audio was clipped.

I used Sony's Noise Reduction 2.0 "Clipped Peak Restoration" successfully to restore the audio.

In other cases, usually when a substantial portion of the audio is clipped, it did not achive the results I needed. But this is to be expected.

Once audio is clipped (more that just occassional clipping) one is lucky to be able to salvage the audio.

If you have just an occassional clipped peak, the Sony's NR 2.0 tools can be very useful. Generally in depends on the nature of the audio.

The three other tools in Sony's NR 2.0 are also very useful.

Some of these tools are very easy to use.

I highly recommend having this tool available.

If you purchase Sound Forge 9, the tools are now included in the package, which cost less than what I paid for the NR 2.0 tools by themselves.

In one case, for unknown reasons, we had some variable high-pitched squeals in some dialog. I do not remember exactly which tool I used, but I was editing with Vegas with NR 2.0, and I was able to extract great audio from the mess!

My Canon XH A1's meters don't always tell the whole story. (note to self: always use headphones...) I recorded a live band at an event by watching my VU meters (am I giving away my age?) The audio was clipped and I normally would have tossed the footage but thought I would see what was available in my "new" version of Adobe Audition. (I've used it since it was Syntrillium's Cool Edit '95) It now includes a Clip Restoration function that provides a few "dials and buttons" in order to adjust the parameters such as input attenuation and overhead. It saved my music clip. If you can't re-shoot (as was my case), it's worth a try.

Well, of course there is no way to completley fix distorted audio, but I'm interested in the part where you mentioned improving the occasional clipped audio.

The best way to "fix" it is to use a good mixer with a limiter so it doesn't clip in the first place.

The Sound Devices 302 and 442 mixers are virtually uncrashable except when operated improperly.

Regards,

Ty Ford

Yes, but that is besides the problem. That is preventing it from happening in the first place. And of course we would all prefer to have prevented it, but that isn't the reality now and we can't go back and change the past. In the future, more care will be taken, but for audio that is already recorded badly and can't be re-recorded.

Apparently there are some decent fixes according to the info given here in this thread, which I'm going to try out. Of course there is no perfect fix that'll make bad audio sound as good as if the audio had been recorded well. That much is obvious. But tips on improving bad audio are always appreciated. And that is the point of these threads/questions.

Being a "major player" means absolutely nothing. I don't care about about these sort of "for fun" ranking systems. It doesn't imply one who is of a different rank is better or more knowledgeable. The only true thing it means is how many posts you have made.

The answer to "How do I fix bad audio?" is never "Just don't record bad audio to begin with." That is pretty much a useless answer analogous to answering the question "Help! I'm pregnant" with "So just don't get pregnant" or answering the problem "I ran out of gas in my car and now I'm stranded in the middle of nowhere! Help!" with "So just don't run out of gas next time. Make sure you watch your gas tank and fill up before it's too late." Not a lot of good that will do after the fact, after the damage has been done already.

No one is disparaging you from your intentions to educate people on how to record good audio to begin with. Those tips are helpful on their own and are appreciated, but it doesn't help in the context of the question of how to improve bad audio. That's all my point is.

OK, time to sit on the deck and drink a few cold ones, whether it's beer or iced coffee. (I make a wicked cold-brewed ice coffee with the Toddy Coffee maker.) I've got a great looking little acre lot, snuggled against a birch forest. Nothing finer than Summer in Alaska:-)

When in a perfect world, we get perfect audio. Last week I was doing backup recording of a small chior in a concert hall. The ventilation didn't get turned off. We were riding the levels hot, too, because there were only 8 voices. The house Neumann's clipped on a loud part, dispite the $$ in equipment. Clipping happens. At least I have my goofy recording using an iPod, Mackie 1202 and 2 AKG Blue Lines to add to the messy audio;-) Yes, that's a crazy setup. I wanted to test the limits of an iPod recorder with the AKGs. I'll post the audio just for fun.

Well, time to throw a few rib-eyes on the BBQ. How many should I throw on for us?

for audio that is already recorded badly and can't be re-recorded, I think the point of this thread was to come up with ways to improve or fix the clipped audio.

Alex,

If you haven't got this sorted, I'm emailing you with my email address and you can send the offending audio to me. I'll see what I can do with it.

Mark

Even better, if this was a staged performance, see if the yell from another take will work.

There's a great piece of software called Vocalign that does a pretty amazing job of realigning (time compressing and expanding) the good take to fit the timing of the bad take. I've seen/heard it; what a life saver. The industry has been using it for years. I wrote an article about it about 10 years ago. At that point the guys in Hollywood said Vocalign was cutting ADR sessions to 30% of what they had been because they were able to use other takes a lot of the time and sync them with Vocalign.

Regards,

Ty Ford

PS Adobe's Audition has been mentioned as a passsable declipper, but most of the reports I've heard say it sort of works, but leaves it's own residue. That's why I didn't mention it earlier. (No one else has either, which tends to make me think it's not really up to the job either) Anyone??

Adobe's Audition has been mentioned as a passsable declipper, but most of the reports I've heard say it sort of works, but leaves it's own residue. That's why I didn't mention it earlier. (No one else has either, which tends to make me think it's not really up to the job either) Anyone??

I use Audition quite a lot and was intrigued by Ty's question above. So I ran a comparison between Audition's clip restoration and the Sony plugin. I amplified a piece of audio by 17db, leaving it mostly clipped, duplicated it and and then ran one through Adobe Audition's inbuilt clip restoration and the other through Sony 2.0's clip restoration plugin (both using Adobe Audition as the base software - this won't affect the comparison between the two plugins). Both plugins had the same attenuation setting. The restored audio tracks came out pretty similar. Adobe Audition's effort did leave one particular strange artefact in just one place, but otherwise I'd say there wasn't much to choose between them. I prefer Adobe audition's plugin because I'm used to it, and it has more user-controllable settings and will produce statistics for you as well. Neither managed to restore the quality of the original but the restored audio was usable.

Digital clipping is a severe effect but also one that software can calculate and at least partially restore. However that's a bit different from my experience of some of the stuff that happens in acquiring sound on a camera. When I first started using my XHA1 with a Sennheiser shotgun mic I always thought it sounded a bit "rough". Then we did one shoot which had quite badly distorted audio even though my colleague said she set the record level set to manual and the meters were looking fine (we were shooting in the middle of a children's playgroup and for safety reasons weren't monitoring on headphones).

In a quiet area, we put the mic on the camera and tried some voice tests, and it still had that subtle "rough" quality - it didn't matter what we did with the level controls or whether the camera was in auto or not. The only thing that cured it - completely - was putting the attenuation in, which for quiet speech I had simply assumed wasn't necessary. I came to the conclusion that this was analogue overload distortion in the camera mic input stages. In the case of the video we shot, the clip restoration plugin didn't make any difference to it. We went back and re-shot this particular piece and now I always use the pad in all but the quietest situations and the sound is a lot cleaner.

For those XHA1 users out there, take a few minutes to do some tests with your mic and don't rely on the meter as I was getting distortion even with the meters only peaking halfway up. If it sounds rough, try it with the pad. The XHA1's inputs seem more than usually sensitive - but are also very good quality and low-noise if set up properly.

Alex,

If you haven't got this sorted, I'm emailing you with my email address and you can send the offending audio to me. I'll see what I can do with it.

Mark


Hi Mark,

I have a file of bad audio from one of my videographers getting a live feed from a band, the connection was dodgy and kept peaking, am l also able to email you a link to listen to it ???

Belinda

Belinda - you did notice he asked the question FIVE YEARS AGO?

Well, it was in a very big building (long echo)
:-)

Belinda - you did notice he asked the question FIVE YEARS AGO?

Ah, there's the rub. We ask people to search the archives before asking a question that's been asked and answered previously. So they search the archives, and indeed they find an old thread that's appropriate. Then they append their new question to the old thread, and are [gently] chastised for their efforts.

Or, to condense: some days you just can't win.

Belinda, start a new thread and post your link here, we can start again and link back to this thread, there'll be feedback like you wouldn't believe.

Cheers.