Audacity Forum

Hi,

I'm quite newbie, so sorry for the lame question, but I hope someone can help me.

So, after I start to record my own voice (will be a podcast), everything is fine (I use just my built-in mic in my laptop), there's a little noise in the background but that's OK since this is an amateur recording. So, after a few seconds, when I don't speak, the noise goes off, as if the laptop wouldn't record, and when I start to talk again, the first syllable I say is weird, it is like the mic just kicked in and started to record again. What could be the reason? I've tried everything, reinstalling soundcard, etc. Nothing has helped. I try to post a picture for the better understanding.

Thank you for your help!

Sounds like you have Auitomatic Gain Control (AGC) turned on for your mic - turn this off and the problem should disappear.

WC

thank you! And where can I find this option? If I go to Control Panel -> Sounds and Audio devices there is no such option. I have a sigmatel audio sound card and the driver doesn't have such option either.

Sorry I can't help you directly with this - my soundcard and drivers are different to yours - and the desktop I am on right now doesn't have an inbuilt mic.

AFAIK you are looking in the right place. My understanding is that the control of such functionality is down to what the Mic and its associate device drivers allow - so you may not be able to control/switch the AGC. Have you got the latest drivers for this Mic? It's possibl that uploading later drivers may help you - no guarantee though.

WC

yeah, I just downloaded the latest, but doesn't work. I think I'll buy an external mic, that should solve the problem At least now I know what is the problem. Thank you for your help!

kbalint wrote:And where can I find this option? If I go to Control Panel -> Sounds and Audio devices there is no such option. I have a sigmatel audio sound card and the driver doesn't have such option either.

The setting will be in the Sigmatel control panel near the clock in the lower right of your desktop.

It may not be called "AGC" there are various names used "Noise Reduction", "Echo Cancellation", "Microphone Enhancement"...
It is often an insignificant looking, hard to find tick box or button. As waxcylinder says, there may not be one, but I have not yet come across a sound card where there was no option to turn it off (though sometimes it could be very difficult to spot).

If you buy a conventional microphone (that plugs into the microphone socket) then you will still have the same issue as the AGC effect is produced by the sound card. If you use a USB microphone then you will not be able to hear your voice through headphones while you are recording - this is not usually a problem, but just to let you know that it is a limitation of USB microphones.

A lot of Podcasters use Sampson Large diaphragm USB recording microphones and get very good results - there's a couple of different models available. Even the cheapest microphone is likely to give better results than the built in microphone.