cutting 'noise' from audio

yanyewkay · 4th January 2007

hi, i'm plagued by a background noise problem.
Currently when I do a recording there's always this 'wind' noise kind of effect. How do I do a clean recording or clean the recorded track?

Chris Lim · 4th January 2007

Originally Posted by yanyewkay

hi, i'm plagued by a background noise problem.
Currently when I do a recording there's always this 'wind' noise kind of effect. How do I do a clean recording or clean the recorded track?

studio recording or location? if its studio recording. choose a spot that the mic is pointing away from the air conditioning. Alternative use the low cut filter and eq it off as much as u can. If that does not work then use a wind sock to slip over the mic. Hmmmm Got one last meathod but may need a little bit of tuning to get it. Which is to use a mic condom to slip over the mic. Has to be pretty tight on so that it acts as a "diaphgram" and does not affect the sound quality too much after cutting off the excessive air con noise. This is however a very very common problem. Just dun gain too high.

yanyewkay · 4th January 2007

on location (indoors), in studio I don't have this problem as bad as i can turn the gain down quite a bit.

shojibake · 4th January 2007

IIRC soundforge has a noise cleaning filter. Or you can use soundsoap which is a lot more friendlier and powerful to use.

But it just sounds like you need to ensure that during shooting the airconditioning is off. Some lights also hum. Also wind noise is just right up there together with voices, so no amount of filtering might be possible other than to have better miking positions.

frenchbean · 4th January 2007

Your main aim should be increasing the Signal-to-Noise ratio, which can be achieved by miking closer to the subject or by using a mic with a narrower pickup pattern. Wind can be mitigated using pop filter. Basically good miking techniques help a lot.

After recording, the noise can be removed using software like Soundforge or Audacity.

I don't like to EQ too much as it tends to make the sound quite unnatural, unless you got a good parametric EQ which can target the offending frequencies, but wind noise is seldom limit to just a few frequencies I think.

yanyewkay · 5th January 2007

thanks guys for the inputs.

Chris Lim · 5th January 2007

use a hyper cardiod mic. like the one i had for sale. MKH 60

josho · 8th January 2007

best to get those good mic cover with lots of 'furs' to reduce ur wind noise. then, u need not to do too much on Eq. Its quite hard to get noise off when its been recorded. It depend where ur mic point to when there's wind.

leekch · 19th January 2007

Need to acertain whether the noise is from the audio circult or from external source.

- audio circuit > microphone inherited noise, impedance mismatch, wrong type of mic cable used, bad contacts between the connectors (oxydation), grounding loop mismatch, recorder's electronic inherited noise, 'dirty' AC current, bad phantom power, mismatch gain structure, etc

- external source > wind noise, vibration near the mic or from the mic cable (eg. floor, someone tapping/stepping on the mic cable), aircon duct vibration, recorder's mechnical noise (cooling fan, motor noise), recording setup placed too close to high power equipment, etc

Is it hiss, hum or rumble?

Hiss > most likely is it electronic inherited noise somewhere in the audio chain
Hum > most likely ground loop problem, impedance mismatch or dirty AC power supply
Rumble > most likely caused by strong moving air nearby the mic, or human breathing into the mic

Try to narrow down and solve.

Good luck.

4th January 2007	#1
yanyewkay Senior Member Join Date: Sep 2004 Location: Cons digger. Posts: 4,046	cutting 'noise' from audio hi, i'm plagued by a background noise problem. Currently when I do a recording there's always this 'wind' noise kind of effect. How do I do a clean recording or clean the recorded track? __________________ “How fortunate for leaders that men do not think.” - Adolf Hitler

4th January 2007	#3
yanyewkay Senior Member Join Date: Sep 2004 Location: Cons digger. Posts: 4,046	Re: cutting 'noise' from audio on location (indoors), in studio I don't have this problem as bad as i can turn the gain down quite a bit. __________________ “How fortunate for leaders that men do not think.” - Adolf Hitler

4th January 2007	#4
shojibake Member Join Date: Dec 2004 Posts: 385	Re: cutting 'noise' from audio IIRC soundforge has a noise cleaning filter. Or you can use soundsoap which is a lot more friendlier and powerful to use. But it just sounds like you need to ensure that during shooting the airconditioning is off. Some lights also hum. Also wind noise is just right up there together with voices, so no amount of filtering might be possible other than to have better miking positions.

4th January 2007	#5
frenchbean Member Join Date: Jan 2005 Location: Singapore, Bedok Posts: 288	Re: cutting 'noise' from audio Your main aim should be increasing the Signal-to-Noise ratio, which can be achieved by miking closer to the subject or by using a mic with a narrower pickup pattern. Wind can be mitigated using pop filter. Basically good miking techniques help a lot. After recording, the noise can be removed using software like Soundforge or Audacity. I don't like to EQ too much as it tends to make the sound quite unnatural, unless you got a good parametric EQ which can target the offending frequencies, but wind noise is seldom limit to just a few frequencies I think.

5th January 2007	#6
yanyewkay Senior Member Join Date: Sep 2004 Location: Cons digger. Posts: 4,046	Re: cutting 'noise' from audio thanks guys for the inputs. __________________ “How fortunate for leaders that men do not think.” - Adolf Hitler

5th January 2007	#7
Chris Lim Senior Member Join Date: Oct 2005 Posts: 3,021	Re: cutting 'noise' from audio use a hyper cardiod mic. like the one i had for sale. MKH 60 __________________ email: Chris@CoffeestainsPhotography.com Website: CoffeestainsPhotography

8th January 2007	#8
josho Senior Member Join Date: Nov 2004 Location: Jln Teck Whye Posts: 2,030	Re: cutting 'noise' from audio best to get those good mic cover with lots of 'furs' to reduce ur wind noise. then, u need not to do too much on Eq. Its quite hard to get noise off when its been recorded. It depend where ur mic point to when there's wind.

19th January 2007	#9
leekch New Member Join Date: Dec 2006 Location: Bt Merah Posts: 40	Re: cutting 'noise' from audio Need to acertain whether the noise is from the audio circult or from external source. - audio circuit > microphone inherited noise, impedance mismatch, wrong type of mic cable used, bad contacts between the connectors (oxydation), grounding loop mismatch, recorder's electronic inherited noise, 'dirty' AC current, bad phantom power, mismatch gain structure, etc - external source > wind noise, vibration near the mic or from the mic cable (eg. floor, someone tapping/stepping on the mic cable), aircon duct vibration, recorder's mechnical noise (cooling fan, motor noise), recording setup placed too close to high power equipment, etc Is it hiss, hum or rumble? Hiss > most likely is it electronic inherited noise somewhere in the audio chain Hum > most likely ground loop problem, impedance mismatch or dirty AC power supply Rumble > most likely caused by strong moving air nearby the mic, or human breathing into the mic Try to narrow down and solve. Good luck.