Videomaker – Learn video production and editing, camera reviews › Forums › Technique › Sound › Removing room noise
August 16, 2006 at 12:05 PM #41100
Hi, need some of your pro advice (again!) for a project.
I recorded someone speaking, at work, with my company’s camera (Sony DCR-HC21) which has no provision for an external microphone. Therefore I’ve got ALOT of room noise that is a distinct part of the audio.
Prior to recording the person speaking, I recorded about 25 seconds of "room noise" and exported all of the audio from Adobe Premiere Elements to Audacity and tried the Noise Removal effect. It removes the hum and the boxy sound but it now sounds "sci-fi" with squeaks and high pitched alien-type noises.
How can a get a nice, clean sound to put back onto the audio track in Adobe Premiere? Thanks for any assistance.
August 16, 2006 at 12:18 PM #175156AnonymousInactive
I hate to say it, but "rerecord" or "overdub" are about the two best options you probably have. And since it sounds like neither are an option, you’ll probably have to keep tweaking the sound until it’s "close enough".
What version of premiere are you using? I know there are some filters in Premiere that do okay, but I’m not sure if they’re in every version.
You can also try to isolate the frequencies that the noise is coming in on and reduce them with a graphic equalizer. If it’s too broad a spectrum, that might not work, but sometimes you’ll at least smooth out some of the more distinct hums and buzzes that way. You can also try to increase the levels that the speaker is the most dominant on, to bring him forward in the mix.
No standard noise reduction software will be perfect. Because obviously that noise is going on even during the speech, software that tries to counteract background noise can only go so far. If you let your filter settings loose a little, you’ll get less "sci-fi" sound, but the background noise will slowly seep in. Ultimately you’ll probably have to try and live with it.
I will say this much. You can get used to a steady hum if it’s not too annoying. Yeah, you lose profesionalism that way, but at least it doesn’t leave your viewer constantly adjusting his hearing.
Sorry, that’s the best I can think of. Maybe someoen else will have better news.
August 16, 2006 at 12:38 PM #175157
Thanks, Jim. This version of Premiere doesn’t seem to have much audio filtering options, from what I could find using the Search feature.
Perhaps I can add some background music at a low volume to mask the sci-fi sounds. And yes, I’ll adjust the frequency levels.
August 17, 2006 at 7:20 AM #175158AnonymousInactive
If you are using Premier Pro, there is one set of audio filters that might help and theyre easy to adjust and use. They are called Highpass and Lowpass.
The Highpass effect removes frequencies below the specified Cutoff frequency. The Lowpass effect eliminates frequencies above the specified Cutoff frequency. What you do is slide these until you sense a drop in background noises but you have to be careful not to start changing the pitch of the recorded voice track. It works for low hums and higher pitch background noise. I find that this comes in handy when working with audio from human dialogue that was recorded in less than perfect conditions.
Using some low volume background music is also a great idea. It will most diffidently help mask out some of the unwanted noise.
Like Jim stated, you can only do so much with audio. The best way of course is to avoid this problem and to take the necessary precautions up front and you won’t have to deal with this headache.
August 17, 2006 at 9:55 AM #175159
Thanks also RAM! I checked Audacity and there is a High Pass and Low Pass filter in the program. Premiere Elements also has them. So, I’m sure that using your suggestions to…
Lower the frequency
Use the High Pass and Low Pass filters, and
Add background music
…the final DVD should be pretty decent and enjoyable. Thanks again!
August 29, 2006 at 2:46 AM #175160CrispieParticipant
In the future, if possible, always use an external mic. I’ve found that for people speaking, lav mics work best. Try and get the mic within twelve inches of their lips.
Turn off all fans, air conditioning and perhaps the refrigerator. Listen for any background noises, hums, traffic, etc.
If you have draperies, pull them shut. It will not only help to keep down the noise from outside, but soft surfaces deal with sound waves much better than flat, smooth sound waves.
Ship any small children, dogs, parakeets, etc. off to Bangladesh or somewhere. 🙂
In fact, consider using clothes line and hanging blankets behind your camera to soften bouncing sound waves. When doing voice-overs, consider using a closet. Hang a blanket just inside the closed door and the hanging clothes will take care of the other surfaces. (This is why clostraphobics don’t gravitate into narration jobs!)
Well it seems you are the best as always +)
August 30, 2006 at 6:19 PM #175161
I applied the suggestions given. The end product, when shown on a television or played in a DVD drive on the computer, came out quite nice. We turned the volume way up on the computer’s speakers and the sci-fi squeaks could barely be detectable. Just 2 of us who knew of the problem recognized that it was there.
However, when it was played from a laptop hooked to a television set with the audio coming through a serious setup with large speakers and sound system, the system channeled every single sound through!! 😮 (!)
Just shows that my journey into the techniques of videomaking has only just begun!!!
August 30, 2006 at 6:29 PM #175162
P.S. Thanks Compusolver for your advice. The camera though, has no input for a microphone so I’m stuck with only the onboard mike for recording sound.
(There is something on the camera called LANC but the manual wasn’t clear on exactly what should be going on there.) 😕
August 31, 2006 at 7:19 AM #175163AnonymousInactive
Your sound discrepancy is a direct result of the type of equipment youre playing the final audio through. When you say a serious setup with large speakers Im assuming that it is a higher end system that will play the entire frequency range from 20 Hz to 20 kHz at a very amplified level. The fact that you were playing this audio through larger speakers that are also probably capable of playing the full frequency range will just make the problem worse because with this set up every little sound sample will be heard no matter if you wanted it or not. You could help yourself if there was a pre-amp equalizer used in which you could turn down some of the frequencies that are making the unwanted noise.
I bet if you were to play this on a normal TV with its default speakers it would sound fine because those speakers dont have as wide of a frequency response thus the unwanted noises would be a little harder to detect.
You probably did the best that you could do but as my distinguished colleague compousolver has already mentioned, (paraphrased of course) An ounce of prevention is worth a pound of cure! Next time youll just have to be a little more careful with addressing the audio. It can be a son-of-a-gun to correct after the fact. 😉
August 31, 2006 at 5:35 PM #175164
Yes, you are correct RAM, the speakers picked up every teensy sound and amplified it all over the room. I had edited the audio using headphones and in the interviews section added in background music to mask the sci-fi sounds. Premiere Elements has a volume control slider which I used to get the volume of the music down so that it wouldn’t compete with the persons talking and this sounded good. But it seemed that even the background music was blasting through this particular set-up.
Just as you said, when played on the television it sounds just right.
Sure, Compusolver is right on spot that I won’t get past audio problems until I get an external mike.
Happily though, the person for whom the video was made isn’t likely to have heavy-duty tripod stands in the family room with large speakers at the top, connected to a soundboard …or …I wonder? X-D I’m kidding, but the next one will be better.
Thanks again for all the advice.
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