Audio Help on Air conditioner background noise at DVinfo.net

Roger Shealy · July 21st, 2009, 05:30 AM

Guys,

I have two short .wav audio clips that have noise from an air conditioner running in the background. I've tried to clean up with Vegas using a band-notch filter, but it doesn't really get rid of all the noise and it's changing the voices more than I'd like.

The A/C noise is centered around 3,000 Hz and is very cyclic.

Anybody have a more sophisticated method for getting rid of the A/C noise without altering the surrounding audio too much?

Jeff Harper · July 21st, 2009, 06:45 AM

I only listened to the first clip but for what it is worth it is not bad, IMO.

It is obviously an AC making the noise, and I would encourage that you not spend too much time on it.

On the other hand if there is a way to remove it I'd like to know what it is also.

Perrone Ford · July 21st, 2009, 06:47 AM

I'll see if I can clean it for you when I get to the office.

Perrone Ford · July 21st, 2009, 07:48 AM

Just listened to the recording.

Wow, yes the noise can be filtered out, and I did it successfully, there is NO WAY it can be done cleanly without affecting the voice. It's similar in frequency and amplitude to the desired signal.

Gonna have to do a much better job next time of getting a clean recording.

Tim Miller · July 21st, 2009, 08:32 AM

I used IzotopeRX on the first clip. It did a good job of getting rid of the hiss and air noise but not the hum. I would be happy to process them and if you are interested.

Gary Brun · July 21st, 2009, 09:38 AM

IzotopeRX is the best I have found for restoration at the moment.

Roger Shealy · July 21st, 2009, 10:21 AM

Tim,

I would appreciate you running them through Izo if you have a moment. I'm not familiar with the program, but would like to see what it can do versus what I have.

Thanks so much for your willingness to help!

James Workman · July 21st, 2009, 11:04 AM

Hey Roger,

I shoot live music in a cafe setting, where I am constantly faced with background appliance noises (icemaker, tea machines, cash register, etc.) I am not familiar with Vegas (I use Premiere Pro), but, if Vegas has a multiband compressor, or a high-pass filter that can be adjusted, OR a "denoiser" that can be tweaked...I have used all of these in the past to reduce appliance noise.

Tim Miller · July 21st, 2009, 11:30 AM

Here is the first file processed. I also fixed some of the clipping issues. Let me know if this works for you.

Perrone Ford · July 21st, 2009, 11:42 AM

Quote:

Originally Posted by Tim Miller

Here is the first file processed. I also fixed some of the clipping issues. Let me know if this works for you.

Wow! That's excellent!

Roger Shealy · July 21st, 2009, 11:58 AM

Tim,

Thank you so much for the great work. The clip sounds really good, I'll have to look into this Izo program. Sent you a PM. You win the superhero award for the week!

Tim Miller · July 21st, 2009, 12:21 PM

Attached is the second file.

This is pretty straight forward with IzotopeRX. You find a little stretch of audio where no dialog is present - just noise. You "train" IRX to recognize the noise pattern by highlighting the "just noise" segment and clicking the "Train" button. Once IRX knows the noise pattern you simply highlight the section of audio you want to clean and click "Apply."

It's a truly amazing app and it has saved my butt more times than I care to admit.

Perrone Ford · July 21st, 2009, 01:48 PM

Quote:

Originally Posted by Tim Miller

Attached is the second file.

This is pretty straight forward with IzotopeRX. You find a little stretch of audio where no dialog is present - just noise. You "train" IRX to recognize the noise pattern by highlighting the "just noise" segment and clicking the "Train" button. Once IRX knows the noise pattern you simply highlight the section of audio you want to clean and click "Apply."

It's a truly amazing app and it has saved my butt more times than I care to admit.

I use a similar feature in another application, but it wasn't nearly as effective as this tool. But the price is rather steep for yours. If I had a TRULY difficult scenario, it would probably be worth it, but generally I only need to remove hiss, and barely audible noise. So my solution tends to work fine for my needs.

Tim Miller · July 21st, 2009, 04:02 PM

Quote:

Originally Posted by Perrone Ford

I use a similar feature in another application, but it wasn't nearly as effective as this tool. But the price is rather steep for yours. If I had a TRULY difficult scenario, it would probably be worth it, but generally I only need to remove hiss, and barely audible noise. So my solution tends to work fine for my needs.

The price is a little steep but it is well worth it to me. I do a lot of work in a local hospital and they don't have the ability to control the air vents in most rooms. I've had footage where it sounded like I was next to a train!

Chris Barcellos · July 21st, 2009, 05:21 PM

Audacity has a very similar filter process in it. Audacity is an open source free sound editing program. Check it out here:

Audacity: Free Audio Editor and Recorder

I did the attached with noise removal. Needs other processing, but it show promise of the program.

July 21st, 2009, 06:47 AM	#3
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	I'll see if I can clean it for you when I get to the office. __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

July 21st, 2009, 07:48 AM	#4
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	Just listened to the recording. Wow, yes the noise can be filtered out, and I did it successfully, there is NO WAY it can be done cleanly without affecting the voice. It's similar in frequency and amplitude to the desired signal. Gonna have to do a much better job next time of getting a clean recording. __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

July 21st, 2009, 08:32 AM	#5
Tim Miller Regular Crew Join Date: Apr 2005 Location: Louisville, KY Posts: 43	IzotopeRX I used IzotopeRX on the first clip. It did a good job of getting rid of the hiss and air noise but not the hum. I would be happy to process them and if you are interested.

July 21st, 2009, 09:38 AM	#6
Gary Brun Major Player Join Date: Jun 2007 Location: Kråkstad Norway. Posts: 229	IzotopeRX is the best I have found for restoration at the moment. __________________ http://www.mlotv.com

July 21st, 2009, 11:04 AM	#8
James Workman Regular Crew Join Date: Jul 2009 Location: Nashville, TN Posts: 43	Multi-Band Compressor? Hey Roger, I shoot live music in a cafe setting, where I am constantly faced with background appliance noises (icemaker, tea machines, cash register, etc.) I am not familiar with Vegas (I use Premiere Pro), but, if Vegas has a multiband compressor, or a high-pass filter that can be adjusted, OR a "denoiser" that can be tweaked...I have used all of these in the past to reduce appliance noise.

July 21st, 2009, 06:45 AM	#2
Jeff Harper Inner Circle Join Date: Jun 2005 Location: Cincinnati, OH Posts: 8,425	I only listened to the first clip but for what it is worth it is not bad, IMO. It is obviously an AC making the noise, and I would encourage that you not spend too much time on it. On the other hand if there is a way to remove it I'd like to know what it is also.

July 21st, 2009, 10:21 AM	#7
Roger Shealy Major Player Join Date: May 2007 Location: Fayetteville, GA Posts: 772	Tim, I would appreciate you running them through Izo if you have a moment. I'm not familiar with the program, but would like to see what it can do versus what I have. Thanks so much for your willingness to help!

July 21st, 2009, 11:58 AM	#11
Roger Shealy Major Player Join Date: May 2007 Location: Fayetteville, GA Posts: 772	Tim, Thank you so much for the great work. The clip sounds really good, I'll have to look into this Izo program. Sent you a PM. You win the superhero award for the week!