Controlling Microphone Audio

[UF_DoC]

Good Day,

I have a USB sound card on my New Pi2 that I use the "mic in" to record audio. The recording is done using the ALSA interface however it is too loud.

I have gone into ALSA mixer and reduced the capture devices "audio" to 0dB but it seems to not make a difference. What am I missing as surely if I drop the MIC input to 0 I should hear no sound at all?

Any advise is appreciated.

Thanks,

[pksato]

Hi,
The sound source is a microphone or a high level source like radio, mp3, etc?
Some microphone have a pre amplifier.

In case of high level source, need to use a impedance match network (attenuator), a potentiometer.

[UF_DoC]

The sound is fed from audio systems line out. Yes I will try a potentiometer circuit of some sort as a last resort.

Im trying to understand why the input is not going off when I reduce the input sound level all the way to 0.

For eg, on my windows machine if I drag the microphone input volume down, no matter how loud the input it will reduce to no sound. why not the same in alsamixer?