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zedx

Member

Registered: 2009-02-02

Posts: 3

Some way to cancel mic noise for all apps(alsa plugin?)

Alright so I've quite a bit noisy mic and was wondering if there could be some way to automatically remove noise(like in audacity) also some way by which I can change pitch, speed etc in realtime for input from the mic (perhaps for the speaker also). That'd be useful when I use voice chat...

zedx

Member

Registered: 2009-02-02

Posts: 3

Re: Some way to cancel mic noise for all apps(alsa plugin?)

None?

thisoldman

Member

From: Pittsburgh

Registered: 2009-04-25

Posts: 1,172

Re: Some way to cancel mic noise for all apps(alsa plugin?)

I think you're looking for something to automatically mute the microphone when you aren't talking, is that correct?  I don't think there's a simple off-the-shelf answer.

One type of plugin used for reducing noise is a noise gate, another is called a 'compander' or 'compansion' (a combination of audio signal compression and expansion).  The voice-altering effect you're looking for is a frequency shifter or possibly a vocoder.

I made quick searches for these effects as alsa plugins and came up empty.  I think there's a way to use ladspa plugins with alsa, but I have no experience with it.

zedx

Member

Registered: 2009-02-02

Posts: 3

Re: Some way to cancel mic noise for all apps(alsa plugin?)

I too couldn't get any significant non-technical stuff. Nothing about noise removal (reduce background/wind noise ) at least. It would be quite helpful if we have such filters easily available...

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: Some way to cancel mic noise for all apps(alsa plugin?)

I guess your best bet is it buy a better or different mic.

Reducing the background white noise (is it white or does it have any other color??) might be relatively straight forward but if the noise floor is too high then your voice may not sound natural because you may be discarding some bits of the spectral content of your voice (but as you want to change it already maybe you don't mind).

Reducing wind noise may be a lot more difficult, the best option is to eliminate its capture altogether, the same goes for background noise, like typing or other people talking, the best way to deal with it is not to capture it in the first place.

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R00KIE
Tm90aGluZyB0byBzZWUgaGVyZSwgbW92ZSBhbG9uZy4K

thisoldman

Member

From: Pittsburgh

Registered: 2009-04-25

Posts: 1,172

Re: Some way to cancel mic noise for all apps(alsa plugin?)

Reducing the background white noise (is it white or does it have any other color??)

I discovered there's pink noise and red noise and gray noise.  I only knew about pink and white noise until today.

zedx, I agree with R00KIE that the best and quickest option is to get a different microphone.

In the meantime, if it is external noise and not electronic noise, try experimenting with microphone positioning.  Move the mic farther away or closer to your mouth, off to the side or directly in line.  Mic position can change the tone qualities, too.  It's a free set of bass and treble controls.

If the noise is electrical or electronic, you might be able to reduce it by keeping the cable and microphone as far away from the computer and other devices as possible.  Fluorescent lights, external drives and power supplies can all put hum into the audio signal.

Another way to  reduce noise and distortion is by careful attention to volume controls.  If there is more than one volume control in the chain, try turning down one level controller and turning up a different one to balance it.  The process is called 'gain staging.'

If you're real serious about sounds and possibly recording, take a look at 'jackd' with 'qjackctl'.  Jackd allows you to connect the output of one audio program to the input of another audio program.  I'll warn you, jack can be complicated and sound effects are sometimes impossible to get working in realtime, with no noticeable lag or stuttering.