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Old December 13th, 2004, 06:48 PM   #1
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Disorted audio - what happened and can I fix it?

I taped a conference last weekend and plugged my camera into the hotel wireless system. I adjusted my levels correctly - to hit right around -12 dB, but the audio is disorted and sounds horrible. I have a brand new camera so I don't think the heads were dirty, so does anyboy have any ideas on what might have happened?

Also - is there anyway I can clean this up, or am I SOL?

thanks...!
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Old December 13th, 2004, 06:56 PM   #2
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What camera where you using? Did you monitor your audio with headphones?

Possibly a hot feed that got overloaded before even recording.

If it is badly distorted (overloaded), I don't know of anyway you can really fix it.
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Old December 13th, 2004, 07:23 PM   #3
 
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Depending on how bad it is, you can try using the Clip Restore plugin/filter in Sound Forge. What it does overall, is to scan for the square waves, and then rounds those particular waves off.
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Old December 13th, 2004, 07:42 PM   #4
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Remember that the meters only show the level of the signal that's being recorded to tape. It doesn't show if your input was overloaded with a hot signal that clipped before it even got to the level controls and the metering. As was stated earlier, the signal could have been distorted before it even got to your camera, but it's more likely that the output of the house system was too hot for the setting of your input (mic, mic att, or line).
What camera did you use and how exactly did you connect to the house system?
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Old December 13th, 2004, 07:45 PM   #5
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I was using a canon GL-2. I monitored the start of the lecture, then stopped b/c everything sounded good.

The wierd thing is that the wireless system was plugged into the house speakers (via XLR) and it sounded fine. I was plugged into the RCA out. I was worried I was plugged into the line out, but there wasn't any markings on the back of the wireless system, only an RCA output and an XLR output.
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Old December 13th, 2004, 10:22 PM   #6
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<<<-- Originally posted by Mark Callahan : I was using a canon GL-2. I monitored the start of the lecture, then stopped b/c everything sounded good.

The wierd thing is that the wireless system was plugged into the house speakers (via XLR) and it sounded fine. I was plugged into the RCA out. I was worried I was plugged into the line out, but there wasn't any markings on the back of the wireless system, only an RCA output and an XLR output. -->>>

Now you know the value of a sound person. We listen to everything, all the time.

If it was all good when you started, maybe somebody bumped your levels while trying to change the camera angle or focus.

What were you listening to when "everything sounded good?"

Sorry for your pain. You might find some relief with Audition. I hear it has a good de-clipper. Next time hire me or a good sounf person in your area. We bring more than good mics. We bring great audio and, most importantly, peace of mind.

(a messsage from your local professional audio sound engineers.)

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Old December 13th, 2004, 10:39 PM   #7
 
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<<<We bring more than good mics. We bring great audio and, most importantly, peace of mind.>>>

If you want our ears, those cost extry.... :-)
Sorry, couldn't help it.

Mark, this is why I have the presentation we do at NAB and other locations; "Audio is 70% of the visual experience." We all know that audio without video is radio, but video without audio is just silent movies.

Hang out here, get some good 'cans, ALWAYS monitor audio, no matter how you do it. I once saw a guy monitoring through a crappy radio set, where his camera was connected to a Radio Shack wireless and he was wearing the accompanying headset, must have sounded horrid, but at least he was listening.

I kinda think that you might have had a line output plugged into a mic input?
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Old December 14th, 2004, 12:13 AM   #8
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all good suggestions. This was my first full conference to be filming and unfortunately I learned the hard way. Of course right as I stopped monitoring the sound, I told myself, "Don't do that, bad idea..." Oops.

The good news is that this gig will pay me enough that I can get a decent set of headphones, better mics, and a small mixing board so I can avoid these issues again. The video looked nice though, but for the format I'm outputting it in, the user won't see the video at all, only the audio!

All of this reminds of a quote I learned while in college - If you think education is expensive, try experience.

Thanks for your suggestions to this newbie! I'm pumped to learn and this forum seems like a great first step.
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Old December 14th, 2004, 05:49 AM   #9
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<<<-- Originally posted by Mark Callahan : all good suggestions. This was my first full conference to be filming and unfortunately I learned the hard way. Of course right as I stopped monitoring the sound, I told myself, "Don't do that, bad idea..." Oops.

The good news is that this gig will pay me enough that I can get a decent set of headphones, better mics, and a small mixing board so I can avoid these issues again. The video looked nice though, but for the format I'm outputting it in, the user won't see the video at all, only the audio!

All of this reminds of a quote I learned while in college - If you think education is expensive, try experience.

Thanks for your suggestions to this newbie! I'm pumped to learn and this forum seems like a great first step. -->>>

Those headphones should be Sony MDR7506, btw.

Ty Ford
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Old December 15th, 2004, 04:21 PM   #10
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best thing>>> do the audio take over! Don't mess with distortion.....that is one of big audio problem which is hardly fixable. You can copy words or certain samples from better takes, so rewind or forward and search for similar words that sound better.

Next time check your volume......buy a cheap mixer to check your volume.
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Old December 15th, 2004, 05:17 PM   #11
 
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Unfortunately in the real world of convention recording/conference recording, it's difficult to get the people that were at the convention/conference to return to the scene of the crime, and even asking them to do so can easily cost a videographer/audio recordist any future work, not to mention the current job. So, you do with what you have, learn from the experience, and move on. Like Mark said, it was a conference, not a controlled shoot.
Imagine going back to the president of your country and telling him that you didn't capture his moment of brilliance in front of the world, and could he please re-do his speech with the same enthusiasm.
Not quite possible.
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Old December 16th, 2004, 03:43 AM   #12
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Yes it is possible. I did a thing like this juse because it was there. It will take you about 8 hours using the waves restoration bundle.
X-noice and the X-crachle then run X-click. You need to run them several times until running them gives you a revesed result. If the picture is nice most customers will not notice. The sound will be a bit harch but usable with the picture.
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Old December 16th, 2004, 08:00 AM   #13
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Unfortunately the video doesn't matter in this case. I'll just be using the audio to create an online presentation based on the speaker's slides.
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Old December 16th, 2004, 01:16 PM   #14
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Restoration has side effects and if you intend to use the audio as a main source, and not as lip sync, it will not be worth the restoration trouble (if it is not slightly damaged that is). The picture lifts the audio to a usable level but I would not suggest to use it stand alone.

Your only option is to rerecord. Sorry!
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