This fancy microphone amplifier module is a step above the rest, with built-in automatic gain control. The AGC in the amplifier means that nearby ‘loud’ sounds will be quieted so they don’t overwhelm & ‘clip’ the amplifier, and even quiet, far-away sounds will be amplified. This amplifier is great for when you want to record or detect audio in a setting where levels change and you don’t want to have to tweak the amplifier gain all the time.
The chip at the heart of the MAX9814 Microphone Module is as the name suggests X9814, and has a few options you can configure with the breakout. The default ‘max gain’ is 60dB, but can be set to 40dB or 50dB by jumpering the Gain pin to VCC or ground. You can also change the Attack/Release ratio, from the default 1:4000 to 1:2000 or 1:500. The output from the amp is about 2Vpp max on a 1.25V DC bias, so it can be easily used with any Analog/Digital converter that is up to 3.3V input. If you want to pipe it into a Line Input, just use a 1-100uF blocking capacitor in series (100uF sounds best).
MAX9814 Microphone Module Technical Specifications
- Supply Voltage: 2.7v-5.5v @ 3mA current
- Output: 2Vpp on 1.25V bias
- Frequency Response: 20Hz – 20 KHz
- Programmable Attack and Release Ratio
- Automatic gain, selectable max from 40dB, 50dB or 60dB
- Low Input-Referred Noise Density of 30nV/
- Low THD: 0.04% (typ)
The title of this device is extremely inaccurate. One gains the impression that with this one module you can connect an input (such as a microphone), connect an output (such as speakers), apply a power supply and all will be taken care of. THIS IS NOT HE CASE. You still need to buy a microphone input device as well as an output board that can handle the current for at least 4-ohm speakers AND a control board such as an Arduino Nano. AND write or obtain a software program that is compatible with the Arduino Java code. Appears to be a classic case of false advertising.
Good day, you are absolutly correct when saying that you need external devices when purchasing this microphone. It is meant to be used in projects along side a micro controller such as the Arduino to achive various tasks such as a VU Meter for example. In this case your micro controller will take the soundwaves it received and process them and depending on the amplitude turn on a number of lights.