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Mic amplifier for ambient sound? Answered

I need a way to pick up distant sound at the mic. I hear output only when i talk too close to mic



1 year ago

How sensitive is the microphone?
How is it set up?
What type of amp are you using?
What is the whole purpose?
Most microphone capsules are designed to only get sound that is very close to avoid getting all unwanted background noises.
Search for directional microphones ;)


Answer 1 year ago

I have no idea about the sensitivity as i have salvaged the mic. However the larger mic has 'CJX' written on it. Both mics produce fairly same results. All i want is to pick conversations, more like hands free kind of thing

20171104_104033.jpg20171104_104426.jpgmicrophone audio amplifier.png

Answer 1 year ago

It comes down to how good the mic is and how well/ strong the amplification is.
For example: if your mic works really well at a distance of 5 to 10cm from the source of sound then all is normal.
Same for not picking much up from a distance of 40cm or more.
The amp has to work with a weak signal generated by the chages in air pressure.
If neither the amp, nor the mic are good for more sensitivity then you can still try to get it to work more directional.
Best option is using a piece of pipe with a similar diameter than the mic.
Place mic at one end and add a few small slots on opposite sides of the pipe.
They are to cancel out noise coming from the sides.
The lenght should be about 20-25 times the diameter of the mix/pipe diameter.


Answer 1 year ago

I have headphones having microphone similar to the smaller one which i have used in the breadboard. When the headphones are connected to the PC, i can hear ambient sound through the headphones. Considering this fact, i also tried to increase the gain of the amplifier to 100 by adding a couple of feedback resistors but still same.

Additional details:

getting 80mV at mic and 2.1V at speaker


1 year ago

Look at the microphone settings. If it has dynamic filtering, turn it off. This feature is meant to do exactly what you'e encountering and it's become pretty normal in "standard" mic enabled apps to filter out background sounds in favor of spoken word (ie for dictation, video and audip conferencing, etc) ..


1 year ago

It depends on why you want this.

IF you want to listen to things far away look up parabolic sound reflector.

Shotgun mike is another name for a similiar idea.

If you want your mic to be more sensitive look for a preamp for it.