Help with Noise Reduction Plug-in

JackW wrote on 2/2/2006, 4:08 PM
I've finally abandoned my several year old version of Cool Edit and downloaded Sony's Noise Reduction Plug-in, the demo version.

I assume that the annoying "beep" sounds that accompany any audio correction are a part of the demo, to go away once the software is registered?

Other than Spot's excellent article on noise reduction, and the numerous helpful posts I've found in the bb archives, is there any single source that discusses the Noise Reduction Plug-in and, for that matter, the other Sony plug-ins (audio and video) in detail?

Jack

Comments

Jessariah67 wrote on 2/2/2006, 5:08 PM
Jack,

Yes, the beeping goes away when you buy the plugin.

Haven't read Spot's article, but I find NR to be as easy to use as it is essential (IMO) to audio cleaning. Grab your noise print and clean away!
JackW wrote on 2/3/2006, 12:54 PM
Thanks for the response, Kevin. I have grabbed, and am cleaning away.

I still find it curious that with all the material that has been written about Vegas, no one has written a book which goes into depth detailing the use of the many plug-ins that accompany the software. Some of these greatly enhance the functionality of an already very functional program, but have to be "discovered" through what can often be a very tedious session of trial and error.

Having a source to turn to, even something like the Vegas documentation that comes with the program, would sure speed up the process.

Jack
Spot|DSE wrote on 2/3/2006, 1:01 PM
Writing a book about plugins would seem to be a useless effort. I've written about noise reduction extensively in two books and a few articles, and maybe once in a blue moon, someone comments or asks about it.
Using the noise reduction tool in Vegas or Sound Forge is very, very easy, almost elementary compared to tools like WAVES XNoise, Bias' Sound Soap, SloTools NoNoise, etc, but still has a lot of flexibility. Rarely, other than changing modes and grabbing smaller vs larger samples, will you change anything in your workflow pattern with Sony Noise Reduction. It just works.
If there is a specific question, I'm happy to answer it, I'm very well versed in NR, as are many people here. Look in the forum for posts from John_Cline, JohnMeyer, and Farss. You'll find lots of great tips, but overall...changing mode and sample size are the only two real variables.
Terry Esslinger wrote on 2/3/2006, 2:46 PM
DSE,
How does the Sony Noise reduction plug in compare to the Audacity (sp?) free program that includes a noise reduction tool?
Spot|DSE wrote on 2/3/2006, 3:05 PM
Like a bicycle to a Ferrari.
Audacity is worth just barely more than what you pay for.
TorS wrote on 2/3/2006, 3:08 PM
One basic tip that may not be so obvious when you start out is to do your reductions in small but several steps. Experiment with steps of 8 - 12 dB at the time. Somehow this method focuses better on the offending noises and leaves more of the wanted audio intact.
Do remember to take a new noiseprint sample after each reduction.

Tor
farss wrote on 2/3/2006, 3:51 PM
Best NR tool I've heard of is from Sony's Oxford division, it raises the bar by being able to track the offending frequencies. This is a pretty important step as if you try to use a very narrow notch filter at a fixed frequency then as the unwanted sound drifts in frequency it'll get missed. One solution is to use a lower Q filter however then you're doing more harm than you strictly need to. This is I suspect what is happening when you use the multiple sample method, it works but the technology exists to make it work much better.
Sadly it would seem that technology is only made available by Sony to Protools users.
Bob.
johnmeyer wrote on 2/3/2006, 4:14 PM
The NR plug-in is good for some types of noise, but not others. The air conditioning hum demo that used to ship with it (maybe still does) is an example of the kind of noise on which it can perform wonders. It doesn't do so well with spikey impulse noise, as I discovered and posted last fall. Wind noise and other forms of broad spectrum noise are also problematic, although the NR can still sometimes help. Often you need to employ not only the small step approach already recommended, but a multi-prong approach, using the Vinyl NR (even for sources other than LP records), the notch filters plug-in, and sometimes the impulse (pop crackle) plug-in.
JJKizak wrote on 2/3/2006, 4:28 PM
On videos without sound I usually add wind noise for background.

JJK
Patryk Rebisz wrote on 2/3/2006, 10:02 PM
So does that mean i should apply NR filter, highlight small section (say 20 frames); reduce the noise and then apply another instance of NR filter to try reducing the noise more????
Spot|DSE wrote on 2/3/2006, 10:24 PM
20 frames is virtually always too much. think more like quarter frames or less.
farss wrote on 2/4/2006, 1:26 AM
I assume if you're using NR2 it's very likely you've Sound Forge. If so SF has a wonderful tool, Spectrum Analysis. Using that to look at your noise can be very helpful.
Thing is, as NR derives its noise profile using FFT, the same as the spectrum analyser, your sample size needs to take into account the frequencies that you're trying to remove. So if you're trying to get rid of something below 100Hz you'll probably need a few frames worth of sample data, something over 4KHz you can use a very small sample. If you don't have SF you can get an idea even withing Vegas by enlarging the waveform (shift + up arrow) so you can hopefully see your noise, aim to get a couple of cycles of it in the smaple window.
Now once you've taken the sample have a look at it! If it's got a lot of spikes in the spectrum of what you don't want to harm then you could run into problems, I sure wouldn't be trying for too much reduction if that's the case so another sample might be in order OR you can modify the noise profile yourself although I wish you could a) enlarge the view and b) it was easier to do.

Last but not least, don't overlook using a noise gate, the one that ships with Vegas is pretty horrid but the Graphic Dynamics that comes with SF is quite usable.

Bob.