Noise detection chip?

[plasmaninjaa]

Hey guys, I dont know anything about audio. So this topic might be in the wrong spot.

I am trying to make something kind of like a hearing aid. I am wondering if something like this will work: Sound Detection Sensor Module Sound Sensor Intelligent Vehicle for Arduino | eBay

I know this is for sound detection, but would i be correct in assuming that if you connect some earbuds to the out and ground pins you would hear sound from the microphone? The quality does not need to be super, just enough to understand words and hear music assuming you could only hear from through the microphone.

if this chip would not work at all, could someone suggest something that would?

I appreciate it!

[Ian Finch]

Hi
The heart of this level switch is an LM393 dual comparator chip. The output of a comparator is not intended as linear amplification of the input signal, but it is generally configured as a level switch. Still, it could give a small amount of audio as described, perhaps enough to drive a larger amplifier or a miniature piezo speaker up to some preset switching threshold. The second comparator likely just latches the LED on at that point.

If you just want a high sensitivity microphone, you would need the schematic and it would be quite difficult but still possible to modify the tiny SMD board so that it had more linear amplification using a dual linear SMD version of an op-amp like an LM358. There are other kits out there for less hassle too, depending on whether it must be an Arduino compatible product and your area and access.

[plasmaninjaa]

Originally Posted by Ian Finch

Hi
The heart of this level switch is an LM393 dual comparator chip. The output of a comparator is not intended as linear amplification of the input signal, but it is generally configured as a level switch. Still, it could give a small amount of audio as described, perhaps enough to drive a larger amplifier or a miniature piezo speaker up to some preset switching threshold. The second comparator likely just latches the LED on at that point.

If you just want a high sensitivity microphone, you would need the schematic and it would be quite difficult but still possible to modify the tiny SMD board so that it had more linear amplification using a dual linear SMD version of an op-amp like an LM358. There are other kits out there for less hassle too, depending on whether it must be an Arduino compatible product and your area and access.

I think linear amplification is more what I am looking for thanks!
do you know of any simple circuits or kits that would do this?

[Ian Finch]

Here is a very simple, ready made mic. preamp. You don't get much for the money but it's a sample of what's out there. You'll need an amplifier to bring the level up from line level to speaker/earbud level as will all preamps. You could adapt it to plug into your PC sound card line input for that, if you don't have the equipment. Alternatively, you could join the preamp with an LM386 opamp for a .5W amplified version to power a speaker. Schematics for that are a Google away too.
FA648: CONDENSOR MICROPHONE PREAMPLIFIER KIT FREE SHIPPING | eBay
Here is a link to the ESP site for good info and designs. There are lots of articles and projects to search and read about there. Main project PCBs are available but not at Chinese prices.
Low Noise Microphone Preamp
Here are some Googled designs for interest but you will need to breadboard them to find how good they are.
microphone preamp circuit - Google Search

Have fun and don't forget to visit our Line and Source forums and search the threads there too. That's where the Mic. topics are.