Fixing poor recorded audio (camcorder built-in)

eL ProduceR

eL ProduceR

Well-known member
Hello everyone, I have been searching for a solution but no luck... yet.

A friend of mine recorded something with his canon hv30, audio recorded with built-in camcorder, there is a long clip where there are people having a conversation but also noise from freeway traffic. I would like to know if there is a way (using Final Cut) to bring down the "background" freeway noise to hear more of the "foreground" audio.

Sorry if I sound to noob... I would appreciate any suggestions.

Be gentle :dankk2:
 
That's a tough gig even using Pro Tools with all the toys. If you don't have noise reduction software start with a low-pass filter, a high-pass filter and a parametric EQ. The low-pass will cut down on hiss (start at about 10kHz and work your way down), the high-pass will reduce the rumble (start at about 80Hz and work your way up), and the parametric will allow you to reduce some frequencies that interfere with the dialog and others that will bring the dialog out a little more (your guess is as good as mine...). Don't expect miracles, it's a lengthy PITA trial and error process even for those of use who are experienced and the results are almost always iffy.

Oh, one more thing, you need a quiet listening environment and some decent speakers.

That's why you use a properly placed quality mic.
 
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Thanks unclebob! (I always wanted to say that!)

I'm going to monkey around with some of the audio filters in FCP; As I have never done any audio work at all, I was totally lost with the high-low pass filters and EQ stuff, something like when I open 3d Studio Max or Cinema 4D :huh: totally lost!!!

I have the feeling I will hear many laughs, but I had the thought that if I had a sample of the background noise (which is constant all the time) I could subtract that from the actual audio and make it cleaner...
 
eL ProduceR said:
Yeah, I think even the dirtiest cheap external mic could have done a better job...
Click to expand...

But it's not as simple as an "external mic." If the highway is behind the subjects, and the mic is on top of the camera, then the mic is pointed at the highway.

Get the mic off the camera and close to the subjects, with a little of that beautiful off-axis rejection taming the highway.

But then there's Rule #1 of shooting for critical audio: buy good headphones and use them while you shoot. Discovering that your audio is a turd once you're in post is discovering when it's too late.
 
:laugh:
eL ProduceR said:
I have the feeling I will hear many laughs, but I had the thought that if I had a sample of the background noise (which is constant all the time) I could subtract that from the actual audio and make it cleaner...
Click to expand...
HAHAHAHAHAHAHAHAHA!!!!!!!!!!!!!!!

There's your laugh!:grin:

The problem is it is not constant, different cars pass by at varying times, at different speeds and distances. Even a machine hum or electronic buzz is wildly variable to electronic "ears", meaning a mic. You would need a perfect, exact copy of the background sound minus the dialog. You could then do a phase invert and you would be left with only dialog.

If you ever see any concert films from back in the '60's you will actually see this technique used - two mics stacked one on top of the other for the singer(s). One mic is out of phase so that when the singer backs away from the mic the stage instruments bleeding into the mics cancel each other out and feedback is reduced. Don't try this on a set; it won't work.
 
C2V said:
But it's not as simple as an "external mic." If the highway is behind the subjects, and the mic is on top of the camera, then the mic is pointed at the highway.

Get the mic off the camera and close to the subjects, with a little of that beautiful off-axis rejection taming the highway.

But then there's Rule #1 of shooting for critical audio: buy good headphones and use them while you shoot. Discovering that your audio is a turd once you're in post is discovering when it's too late.
Click to expand...

Thanks for your advice C2V, I understand the basics of proper audio recording thanks to some trial and error experience in the past... I agree with the headphones tip, however, when recording from two different sources (boom and handheld or lav) I usually find it hard to monitor left and right at the same time
 
unclebob6958 said:
:laugh:
HAHAHAHAHAHAHAHAHA!!!!!!!!!!!!!!!

There's your laugh!:grin:

The problem is it is not constant, different cars pass by at varying times, at different speeds and distances. Even a machine hum or electronic buzz is wildly variable to electronic "ears", meaning a mic.
Click to expand...

Interesting fact, I though of "noise" as belonging to certain kHz level. But even killing something as whatever level (the freeway noise) will affect the conversation and other sound elements in the audio, right?
 
To sort of mimic the rest YES, the freeway is broadband and constantly varying. You can sort of eliminate it with NR plugins IF it is VERY distant, but yours isn't or it wouldn't be interfering with the dialog. I had to deal with a scene like this and it worked OK, I continued all the car by's so the cuts disappeared but then it was WAY too much traffic so we ADR'd the whole scene. There is a before and after on my site,
Cheers
SK

Scott Koue
www.scottkouesound.com
http://imdb.com/name/nm0468138/
 
eL ProduceR said:
killing something at whatever level (the freeway noise) will affect the conversation and other sound elements in the audio, right?
Click to expand...
Absolutely. Whatever you do is going to affect the dialog as well as the noise. What you are doing - in essence - is trying to take the cherry out of a cherry coke. Your best hope is that it will go from incredibly crappy to just really bad.
 
unclebob6958 said:
Absolutely. Whatever you do is going to affect the dialog as well as the noise. What you are doing - in essence - is trying to take the cherry out of a cherry coke. Your best hope is that it will go from incredibly crappy to just really bad.
Click to expand...

I did not want to sound mediocre, but believe it or not, that's what I'm trying to accomplish, the audio is in really bad shape... I will try to post some of it if possible, if my friend lets me, the content is kind of sensitive to him, thanks ub
 
eL ProduceR said:
... I agree with the headphones tip, however, when recording from two different sources (boom and handheld or lav) I usually find it hard to monitor left and right at the same time
Click to expand...

And now you know why better quality field mixers have a headphone output that is switchable between monitoring stereo, or left channel only to both ears, or right channel only to both ears, or summed left and right channels to both ears, etc.
 
Bad audio happens, just re-recorded in a clean env and have someone with protools rig and vocalign put it together. It works really well, even put a highway noise track(at a diminished volume) to give it atmosphere. I'll do it...for a fee. ;)
 
eL ProduceR said:
I did not want to sound mediocre, but believe it or not, that's what I'm trying to accomplish, the audio is in really bad shape... I will try to post some of it if possible, if my friend lets me, the content is kind of sensitive to him, thanks ub
Click to expand...

You will probably have to ADR.

You can get it cleaned up beautifully. A friend of mine does forensic audio. He charges $375 per hour, and it usually takes 90 minutes to three hours per minute of audio to be cleaned up. So let's see, a five minute scene will take, oh, call it twelve (12) hours; that's only $4,500. A real bargain!

Sorry, I didn't mean to be so sarcastic, but what you are trying to attempt will be extremely difficult and time consuming, especially since you don't have the tools or the experience, and the results will probably be equivocal. Let this be a lesson to your friend; you have to plan out your sound as well as the visuals prior to shooting. This means scouting locations for sound as well as its look.
 
Lol, guys, this is six-pack-Joe's-weekend-in-the-park kind of footage recorded with an Canon HF200, just needed some tips to clean up the audio a bit so Joe could hear his cousins saying hello to grandma.

I played around with the High pass filter and Low pass filter and boy, it went from really, really crappy to kind of crappy. You can still hear the freeway noise, but the conversation is more distinguishable. Thanks for your tips guys, really, thanks
 
Steve House said:
And now you know why better quality field mixers have a headphone output that is switchable between monitoring stereo, or left channel only to both ears, or right channel only to both ears, or summed left and right channels to both ears, etc.
Click to expand...

Sounds like a sweet feature to have on a ENG type of camera.
 
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Yeah, just save the aggravation of trying to clean it. I would re-record and stretch it in there, the grandmother is probably old, she won't notice.
 
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