Jump to content


CM-311A: how to avoid breath noise


  • Please log in to reply
6 replies to this topic

#1 Vincent Timmermans

Vincent Timmermans
  • Members
  • 1 posts

Posted 23 July 2007 - 02:06 PM

Hi,

I just bought a CM-311A and I'm having trouble with pops and breath noise.

The manual says that I'm supposed to push the filter against my lips and indeed this way the pops are almost unaudible. But how am I supposed to articulate clearly with a piece of foam restricting the movement of my lips? And further more, in this position, I'm hearing a lot of breath noise from the nose.  sad.gif

The knowledgebase says that I should use a high pass filter to get rid of the low frequency pops and breath noise, but having to record male voices, I can't seem to find a setting that does not have an impact on the richness of the sung tones, especially for the lower parts.  huh.gif

I also tried to move the mic away from the center of my mouth, but (maybe it's just the way my face is built) I have to move it to the side all the way to get rid of the breath noise. And then there is a serious impact on the input gain and quality of the sound.  ohmy.gif

Is there a solution or is a headset just not for me and should I bring it back and buy myself a decent (Crown) handheld mic?

Any suggestion is welcome!

Vince

#2 MChapman

MChapman

    Power User

  • Members
  • PipPipPipPipPip
  • 126 posts

Posted 09 August 2007 - 12:56 PM

Vincent,

You have discovered the age old paradox of using a mic very close. While the gain is great, you can also pick up the sound of your own breathing. This is more of a problem with head worn microphones, because you can't back away from the mic. Many of the professionals using our mics have fixed this problem by careful balance of location to pick up the audio but to diminish the breath noise. This may require moving the mic up or down on the mouth, and even off to the side of the lips. Because of differences in each of our sinus's physical behavior, this may not give you the desired results. Sometimes, more drastic measures are needed, such as adding a noise gate in the signal path that will remain "closed" while you are not talking or singing, and will only "open" when the desired audio level is achieved.

J. Mark Chapman
Application Support

<span style='color:blue'>J. Mark Chapman
Crown Application Support Technician</span>

#3 brubart

brubart

    Power User

  • Members
  • PipPipPipPipPip
  • 52 posts

Posted 10 August 2007 - 08:30 AM

Hi Vincent,
You mentioned that you are using the CM-311A for recording. That mic is really intended for PA applications, where breath sounds are usually hidden in the background noise of the venue. For recording vocals I'd suggest the Crown CM-700 or AKG Perception 100 cardioid condenser mic.  A typical placement is 8 inches from the mouth with a hoop-type pop filter between the mic and singer to prevent breath pops.

If you hear too much room acoustics in the recording, add some pressed-fiberglass panels (covered in fabric) or acoustic foam to the room.

Are you using a headworn mic to reject background noises? A conventional mic at 4 to 8 inches from the mouth should not pick up too much noise when the vocal track is mixed with the music tracks.

Good luck,
brubart

#4 EllenA

EllenA
  • Members
  • 1 posts

Posted 20 February 2008 - 09:40 PM

I too intended to use this microphone for recording - it sounded like it would be great for recording the audio portion to accompany my screencasts and video tutorials. I need hands free operation and a microphone that 's not in th way of my computer and keyboard.  But the breath sounds are are a major problem.  I am essentially clueless as to most things related to audio recording, so how do I go about adding a "noise gate in the signal path?"

Are there any other solutions?

QUOTE(MChapman @ Aug 9 2007, 12:56 PM) View Post
Vincent,

You have discovered the age old paradox of using a mic very close. While the gain is great, you can also pick up the sound of your own breathing. This is more of a problem with head worn microphones, because you can't back away from the mic. Many of the professionals using our mics have fixed this problem by careful balance of location to pick up the audio but to diminish the breath noise. This may require moving the mic up or down on the mouth, and even off to the side of the lips. Because of differences in each of our sinus's physical behavior, this may not give you the desired results. Sometimes, more drastic measures are needed, such as adding a noise gate in the signal path that will remain "closed" while you are not talking or singing, and will only "open" when the desired audio level is achieved.

J. Mark Chapman
Application Support



#5 brubart

brubart

    Power User

  • Members
  • PipPipPipPipPip
  • 52 posts

Posted 29 February 2008 - 02:30 PM

QUOTE(EllenA @ Feb 20 2008, 10:40 PM) View Post
how do I go about adding a "noise gate in the signal path?"


A noise gate turns down the volume during pauses in speech, so it reduces breath noises. Noise gates are available in hardware or software. Some manufacturers are Drawmer and Alesis, among others.

To use a hardware noise gate,
1. Plug the mic into a mic preamp or small mixer that has phantom power.
2. Connect the output of the preamp or mixer to the noise gate input.
3. Connect the noise gate output to your sound card or audio interface line input.
4. While talking, adjust the gate threshold so that breathing during pauses is inaudible but speech is not gated or cut off.

To use a software (plug-in) noise gate in a recording program, insert it into the track that your speech is recorded on. While playing the track, adjust the gate threshold as described above.

Ideally you would use a headworn mic in which the mic capsule is to the side of the mouth to prevent breath pops. Crown no longer makes one, but you could make one by taping a Crown GLM-100 mini mic ($185) to a bent coathanger wire that goes around your head and over both ears, with a "boom" extending from one ear to the side of your mouth. A diagram is here: http://www.crownaudio.com/kb/entry/320/

Good luck!

brubart


#6 fbtool

fbtool
  • Members
  • 2 posts

Posted 08 March 2009 - 12:55 PM

You might experiment with a small piece of clear or colored adhesive tape across the top of the wind screen. The breathing noise comming from your nose is then kept from blowing across the mic.
FB.

#7 MikeThePianoman

MikeThePianoman
  • Members
  • 1 posts

Posted 16 November 2009 - 11:42 PM

QUOTE(fbtool @ Mar 8 2009, 12:55 PM) View Post
You might experiment with a small piece of clear or colored adhesive tape across the top of the wind screen. The breathing noise comming from your nose is then kept from blowing across the mic.
FB.


This seems to be an excellent suggestion and I am curious if you have actually tried this. Is this a known solution in the audio community? I also see that Crown Staff participates in this forum - do you have comments on this? A windscreen accessory product to provide this would be excellent.

Just to clarify for me - the breathing from the mouth straight out into the mic seems to be no problem. The noise from the nostril breathing is unbearable.

Also, I have tried using the mic slightly off the lips (Crown recommends on the lips). Off the lips seems to work fine with more freedom it seems.....