View Full Version : Audio Problems with Wedding Video


Chris Wright
August 18th, 2004, 09:01 PM
In short, I made a stupid mistake, and I'm hoping you guys can help me fix it :)

The wedding I shot two weeks ago seemed to go very smoothly. It was held at the church that I attend, and I know the audio guy. He gave me a line out cable to my camera from the sound board that gave me the audio from the pastor's mic and the piano. Perfect. well, I tested it with the GL2 during the rehearsal, sounded fine through the headphones. However, during the wedding the camera recording this audio was an Optura 500 instead. Of course, I forgot the headphones on the day of the wedding (I know I'm stupid, you don't need to tell me again). Since I had no problems with the GL2, I just set up the Optura the same way.

Now, after the wedding, I find that the audio has a low buzz over it. The audio picked up and sounds fine (really good, actually) ...if only I could get rid of that damn buzz. Is there a way to reduce this in FCP and still retain a useable audio signal?

Also, one of my other cameras was placed next to a speaker that was playing the same audio signal sent in to the Optura. It picked up all the music perfectly, but the voices - the pastor's, specifically - seemed somewhat "muddy" and had a sort of echo to it. It does not sound near as good as my line in audio under the buzzing noise.

If anyone could help me either reduce the buzzing from the Optura's audio or tweak the audio from the other camera to reduce the echo, I would greatly appreciate it. However, I know that as a general rule, you can't do much to fix bad audio, so I'm not expecting a miracle here, but its always worth asking!

Glenn Chan
August 18th, 2004, 10:20 PM
If it's buzz from a ground loop you might be able to reduce the buzz with a comb filter.

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You probably need to export your audio to an audio app, especially if you don't have FCP4.

Phil French
August 18th, 2004, 10:32 PM
I have had great success using FCP's Hum Remover filter.

First you have to figure out the frequency of the buzz. Open your clip in viewer and look at the wave form of the buzz in a part of the clip where it is isolated. Zoom in to max and count the number of cycles in one frame. Multiply the number of cycles per frame by 30 to get the cycles per second. Enter this number as the frequency in the Hum Remover filter that you have dragged into your clip. Check off the first harmonic for good measure and render. This should remove the buzz or hum without damaging your other audio.

I hope this works for you. Good luck!

Chris Wright
August 19th, 2004, 06:27 AM
thanks so much for your help... that really looks promising.

I do have Final Cut Pro 4 (HD) as well as Peak DV 3 (which I think came bundled with FCP 3). If you guys think I'll have better luck in peak, I'll try that. If not, I'll try the comb filter or hum remover.

Unfortuneately, the audio track I'm talking about is still on a DV tape, and , my GL2 is being sent in for repair :(
who knows how long it will be before I can import this tape and try to fix it. Maybe I can borrow a friend's DV camera...

thanks again!
Chris

Patrick Grealy
August 23rd, 2004, 11:07 AM
Would suggest that you get the audio file into an audio app like Logic and then use some sharp equalisation to reduce the buzz (parametric EQ with a sharp Q Value).

You might be able to get decent results with only slight artifacts (which could be covered up with the good background feed you have from the PA)

Regards P

Dean Sensui
August 24th, 2004, 03:34 AM
Chris...

Try the hum removal filter in FCP 4. There's options to select harmonics, too, and certain combinations of those settings might work, too.

I had a couple of clips from other sources which had a 60 hz hum and this filter made it passable. Not great, but not horrible, either.

Dean Sensui
Base Two Productions

Duane Martin
August 25th, 2004, 10:26 AM
I have completely fallen in love with Bias software's SoundSoap. If you have three seconds of noise without people speaking, it will clean that audio like you could if you were a pro. I am always hassling videographers to make sure they have given me a "room tone" from any event so I can take advantage of the excellant auto cleaning feature of SoundSoap.

It can be adjusted manually as well, but again, I don't want to know what is doing or how it is working. I just want the noise gone.

Chris Wright
August 25th, 2004, 12:10 PM
that soundsoap sounds interesting... do you know if there is a Mac OS X version of it, and how much it costs?

Also, I have been trying the hum remover and parametric EQ filters mentioned here, as well as the 3 Band Equalizer... and havent had much luck. I think the buzz may be too loud in the first place, and it just won't go away

Oh well...

Duane Martin
August 25th, 2004, 01:52 PM
Chris, I would suggest Googling SoundSoap for answers.