• The default 'max gain' is 60d B, but can be set to 40d B or 50d B by jumpering the Gain pin to VCC or ground• You can change the Attack/ Release ratio, from the default 1:4000 to 1:2000 or 1:500• The output from the amp is about 2 Vpp 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 1u F blocking capacitor in series 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, & 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 & you don't want to have to tweak the amplifier gain all the time. The chip at the heart of this amp is the MAX9814 If you just need to keep track of audio levels, see this sound-level meter tutorial for Arduino found here Each order comes with one assembled & tested board, with an electret mic pre-soldered on, & a small piece of header. Adafruits tutorial will get you started with using & testing the microphone amplifier & you can check out their general-purpose microphone amplifier tutorial for other project ideas & code