Electret Microphone Amplifier — MAX4466 with Adjustable Gain

$40.5 $68.85
Add an ear to your project with this well-designed elec­tret micro­phone ampli­fi­er. This ful­ly assem­bled and test­ed board comes with a 20–20KHz elec­tret micro­phone sol­dered on. For the ampli­fi­ca­tion, we use the Max­im MAX4466, an op-amp specif­i­cal­ly designed for this del­i­cate task! The ampli­fi­er has excel­lent pow­er sup­ply noise rejec­tion, so this ampli­fi­er sounds real­ly good and isn’t near­ly as noisy or scratchy as oth­er mic amp break­outs we’ve tried!This break­out is best used for projects such as voice chang­ers, audio recording/sampling, and audio-reac­tive projects that use FFT. On the back, we include a small trim­mer pot to adjust the gain. You can set the gain from 25x to 125x. That’s down to be about 200mVpp (for nor­mal speak­ing vol­ume about 6″ away) which is good for attach­ing to some­thing that expects ‘line lev­el’ input with­out clip­ping, or up to about 1Vpp, ide­al for read­ing from a micro­con­troller ADC. The out­put is rail-to-rail so if the sounds gets loud, the out­put can go up to 5Vpp!Using it is sim­ple: con­nect GND to ground, VCC to 2.4–5VDC. For the best per­for­mance, use the “qui­etest” sup­ply avail­able (on an Arduino, this would be the 3.3V sup­ply). The audio wave­form will come out of the OUT pin. The out­put will have a DC bias of VCC/2 so when its per­fect­ly qui­et, the volt­age will be a steady VCC/2 volts (it is DC cou­pled). If the audio equip­ment you’re using requires AC cou­pled audio, place a 100uF capac­i­tor between the out­put pin and the input of your device. If you’re con­nect­ing to an audio ampli­fi­er that has dif­fer­en­tial inputs or includes decou­pling capac­i­tors, the 100uF cap is not required.The out­put pin is not designed to dri­ve speak­ers or any­thing but the small­est in-ear head­phones — you’ll need an audio ampli­fi­er (such as our 3.7W stereo amp) if you want to con­nect the amp direct­ly to speak­ers. If you’re con­nect­ing to a micro­con­troller pin, you don’t need an ampli­fi­er or decou­pling capac­i­tor — con­nect the OUT pin direct­ly to the micro­con­troller ADC pin.TECHNICAL DETAILSEagleCAD PCB files on GitHubMAX4466 Low-Noise Micro­phone Amp DatasheetElec­tret Cap­sule Micro­phone DatasheetFritz­ing object in Fritz­ing library
Sound

Sound