In countries on the 60hz system, "hum" is only at 60hz, however, "buzz" is at 60hz plus a bunch of harmonics of 60hz; 120hz, 180hz, 240hz, 300hz, 360hz, 420hz, etc. If's it's just hum, a narrow filter at 60hz will do it, if it's buzz, you will need to filter out the fundamental at 60hz plus each of the offending harmonics. Typically (but not always,) 60hz will be the loudest with each higher harmonic being lower in amplitude.

John

Is there a link someone can direct me to that is a handy tutorial for using the Noise Reduction filter or other filters just mentioned?

Probably, but I don't know it. But there is a very useful "search" feature on this board that will get you all kinds of hits, and at least one of them will get you what you need.

Okay. Thanks; I'll try searching this forum again. Dale

Take a look at the waveforms. There are three alternatives that I have used, two of which have been mentioned.

1. Use notch filters at 60 Hz. plus it's harmonics. Use the spectrum analyzer (in Sound Forge) to see how strong the harmonics are in order to determine how high up in frequency you must go.

2. Use the NR plug-in. If the noise is strictly line-related, #1 above is a better approach, but if it isn't, or if there is still residual buzz, then use NR.

3. If you can see repetitive spikes in the audio waveform, probably at 60 or 120 Hz intervals, you can actually get MUCH better noise reduction by NOT using either of the previous methods. See my thread on this subject here:

Continuous Impulse Noise (Buzz) Reduction

I just re-read that entire thread. The people that participated in that thread are top-notch, and virtually every post should be useful to you in fixing your problem.

thanks for your time.

John, that's an excellent thread. Obviously I'll have to get into the habit of searching all forums when looking for solutions.

Sony Noise Reduction is first rate. I've also had success with some of the NewBlue audio FX.

http://www.newbluefx.com/audiofx.html

Darryl

Firt rate indeed! And usually it works best when you make several passes, reducing only a little each time (say 8 dB or so). Do remember to take new noiseprints each time.
Tor

NR is excellent but JohnMeyer is recommending a different technique for the buzz problem. That's what was so interesting about the posted thread.

NR is excellent but JohnMeyer is recommending a different technique for the buzz problem.

First thanks for the kind words about the earlier thread. That was the forum at its best. The answers there were truly useful.

As for the different techniques (there were 2-3 different ones, beyond the usual NR and EQ techniques), I am only recommending them IF the waveform shown on the Vegas timeline reveals the the noise is largely from a repetitive spike. My situation was something I hadn't seen before or since, namely a really sharp spike, like you'd see on an oscilloscope when working with a light dimmer (something I have actually done). When the triac fires, you can get huge, instantaneous spikes.

If the original poster has any silent, or fairly quiet sections to look at, those should show the noise. If that noise looks "rounded," then the alternative techniques presented in that thread will probably not work.

Another great program is Audacity. Even greater cuz it's free! = )

I got some unusual buzzing during a wedding reception a few months ago. It was on only about 5 minutes of footage. I wasn't using a wireless mic or anything, and the buzzing wasn't heard in the room. It hasn't happened before or since.

Either way, Audacity took it out with no problem. The DJ's speaking, then a lady translates what he's saying into Chinese (I believe).

Buzz Before and After

That's a remarkably good result!
Having gotten rid of the noise some echo reduction might be in order.

Know I've mentioed this before but worth repeating.
I've had good results also using the Click and Plop Removal FXs in SF on fast transient noise. Seems to tame sample rate errors if nothing else but always worth a try.

Bob.

It sounded echo-y even in the non-buzzing fotage. The acoustics in the room weren't very good, along with the noise of the people and utensils clanking on plates.

That's the only good thing about a consistent buzz, in that it's easy to isolate, where ambient chatter isn't.

But it's great to have tools to combat the problem. Years ago if this had happened, I'd pretty much be screwed.

There is a way to reduce that echo if you want to give it a go. Takes a bit of fiddling around but sometimes it works pretty well.

Make another copy of the audio track and invert it. Net result should be silence. Now apply compression to one of those tracks.
You will have to adjust the threshold and the compression ratio until you get the best result. The aim is to get the treshold just above the level of the echo.

How it works is this. The compressor will not affect the echo as it's below the knee so the echo is cancelled out. The wanted part, in this case the speech, will be affected and hence will not cancel out completely.

This is a very old trick. It's not perfect but can do wonders.

Bob.

i just had a orporate client who insisted on shooting near the lunchroom and near 2 loud PC's so i had so many issues with audio it wasnt funny

I ended up doing this (as a filter chain)

2x noise reduciton (dont ask.. i usually dont do this but it makes a difference.. ) vynil restoration (to get rid of that hun

Sony express fx to bring back the lost high end detail, tone2B resonant filter to clean out the dialogue with a parametricEQ widened at teh high end with teh cut of set at + 17k hz gets rid of low end rumbles but not the bass in vocals
Then im running beatmodel optiverb to thicken the vocals and "wash" out the ambient background noise. The reverb is tight and brings out the midrange without peaking the higher ends. Then ive got beatmodel OptiEQ to bring back the high end which is lost by using the Tone2B, the graphic EQ for basic EQ, smooth enhance filter coz it jsut needed that "somethign" and finaly wavehammer to bring everythign back to level...
Under than im running a breakbeat/trance soundtrack with the vocal frequencies of teh dialoge cut, this way, the music and dialoge arent sharing the same frequencies..

this is prolly the most difficult audio restoration ive done considering the locaiton and the fact that noone gave a shit about being quiet.. I think i pulled it off though.. but when u consider how much time ive just spent fixing this.. either way, if they listened to me, there wouldnt have been an issue, but then again, some corporate clients have their own ideas that you cant argue with (if u want to get paid that is)

Well, in listening to that noise reduction, while you managed to get rid of the buzz, you are left with a tremendous amount of that "crinkly" and "echoey" stuff (I think the audio folks call it flanging). Still pretty annoying. If you instead take a sample of the buzz from a relatively quiet passage (there is a really good sample just as he starts the introduction), invert that, replicate it in Vegas, and then "tune" it by zooming all the way in on the noise sample and dragging it back and forth while looping, you can get near-perfect noise reduction. Since the noise isn't absolutely constant, you have to break the noiseprint into sections in Vegas, and tune each section separately. I didn't have much time on this, so you will hear where the noiseprint starts to drift and the noise reappears. What you should concentrate on are the sections where the noise is almost gone. If I had more time, I would have broken the noiseprint into smaller sections.

I did absolutely no other noise reduction on this sample. If I had more time, not only would I break my noiseprint into smaller sections, but I would have used EQ, using notch filters at 60, 180, 300, etc. (the noise is exactly the odd harmonics of 60 Hz.). You don't need to do all of those -- only some of them are obnoxious. When finished, you could still do some LIGHT cleaning using the noise reduction plugin you used initially. You could then try the echo cancellation that Bob described.

Here's the noise-reduced clip. Again, you will note the the noise comes and goes a bit, because I didn't have the time to tweak it.

Noise Reduced Using Inverted Noise Print

Link good for seven days.

You're right, there is flanging in my sample. With yours, while you got the buzz reduced, it's still there. This is a project that's already finished. I was just adding my two cents that Audacity is another option. I tweaked it a tad more, but what you hear is basically what they got. While far from perfect, it was a big improvement over the original.

This was an asian wedding reception that had over 400 people in the banquet hall for dinner, along with bad acoustics, which made it difficult to get a "clean" buzz sample without the backround noise. Even the good footage doesn't sound that great, so any flanging wasn't really that noticable in the big picture, at least to the client.

Does anyone have Soundsoap 2.1? Demo movie.

It looks interesting as it can be used as a VST plugin to Vegas. (VMS in my case.)

I can't decide if I just want to get NewBlue's Scrubber FX for $49.95 or get Soundsoap for $99 at a local store.

Does the "M" stand for Maxwell?

Anyway, Sony Noise Reduction will do a far, far better job than Scrubber, believe me. Remember, you get what you pay for!

Does the "M" stand for Maxwell?

Yes, how did you know? You're not from KAOS are you?

Anyway... I have VMS 7 Plat and either I'm blind or it doesn't have a NR filter. The closest thing I could see is "ExpressFX Audio Restoration" that had noise reduction as an option.