This electret capsule microphone is the same one we use in our great microphone amplifier board. It contains a small vibrating element that will output a few milllivolts peak-to-peak. You will need an op-amp to amplify the signal, some chips are designed with the amplifier built in in which case you can wire it up directly.

This is an "omnidirectional" microphone, with -44dB sensitivity, and has 20-20KHz frequency response. You can plug it into a breadboard or perfboard or solder wires to the little wires sticking out the back.

Check out OpenMusicLab's great tutorial on Electret Microphones for a deeper look at how these sensors work. If you need an amplifier board, see our fully-assembled and tested mic amp board with adjustable gain.

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.For audio-reactive Arduino projects, we suggest using an FFT driver library (such as the one in this library) which can take the audio input and 'translate' it into frequencies. Also, check out this awesome Voice Changer project that uses this mic and an Adafruit Wave Shield!

If you're using with CircuitPython, this audio-reactive pendant project is pretty easy and works great with any CircuitPython board.

This is a small 12mm round speaker that operates around the audible 2kHz range. You can use these speakers to create simple music or user interfaces.

This is not a true piezoelectric speaker but behaves similarly. Instead of a piezoelectric crystal that vibrates with an electric current, this tiny speaker uses an electromagnet to drive a thin metal sheet. That means you need to use some form of alternating current to get sound. The good news is that this speaker is tuned to respond best with a square wave (e.g. from a microcontroller).

This tiny breakout board features the ADMP401 MEMS microphone. One of the key advantages to this breakout and microphone is the bottom ported input. This means the microphone’s input can fit flush against the enclosure of your project. Plus you will not have to deal with trying to solder the microphone’s wacky footprint. Wootness!

The amplifier on the breakout has a gain of 67 and more than meets the bandwidth requirements of the mic. The amplifier’s AUD output will float at one half Vcc when no sound is being picked up. The amplifier produces a peak-to-peak output of about 200mV when the microphone is held at arms length and is being talked into at normal conversational volume levels. So the AUD output can easily be connected to the ADC of a micro.

Get Started with the ADMP401 Breakout Guide

Features

-3dB roll off at 100Hz and 15kHz

1.5 to 3.3VDC supply voltage

Should comfortably output 40mW

SNR of -62dBA

The SparkFun MIDI Shield board gives your Arduino-based device access to the antiquated, but still widely used and well supported MIDI communication protocol, so you can control synthesizers, sequencers, and other musical devices. The MIDI protocol shares many similarities with standard asynchronous serial interfaces, so you can use the UART pins of your Arduino to send and receive MIDI’s event messages.

The SparkFun MIDI Shield provides an opto-isolated MIDI-IN port as well as a MIDI-OUT port. The MIDI Shield can be mounted directly on top of an Arduino, connecting the MIDI-IN to the Arduino’s hardware RX pin and the MIDI-OUT to TX. Potentiometers are connected to analog pins 1 and 2, and can be used to control volume, pitch, tone or anything else you’d like. The shield also comes with three momentary push buttons, a reset button, and green and red stat LEDs. The RUN/PROG switch allows you to program the Arduino over serial without having to remove the shield.

This revision of the SparkFun MIDI Shield also adds several configurable features, such as converting the MIDI output to a MIDI thru, and the option to use a software serial port for MIDI, leaving the hardware serial for programming and debugging. It also buffers the output, making it compatible with the Arduino Pro without needing to circumvent the protection resistors on the serial TX and RX lines.

Note: The MIDI Shield does not come with all parts soldered on. Two MIDI connectors, two trimpots, and three pushbuttons are included with the product and will need to be attached by the end user.

Includes

SparkFun MIDI Shield PCB

2x 5-pin DIN conectors

2x 10K rotary potentiometer

3x 12mm tactile pushbutton switches

The SparkFun MP3 Player Shield is an awesome MP3 decoder with the capabilities of storing music files onto a run-of-the-mill microSD card, thus giving you the ability toadd music or sound effects to any project. With this board you can pull MP3 files from an microSD card and play them using only one shield, effectively turning any Arduino into a fully functional stand-alone MP3 player! The MP3 Shield utilizes the VS1053B MP3 audio decoder IC to decode audio files. The VS1053 is also capable of decoding Ogg Vorbis/MP3/AAC/WMA/MIDI audio and encoding IMA ADPCM and user-loadable Ogg Vorbis.

The VS1053 receives its input bitstream through a serial input bus (SPI). After the stream has been decoded by the IC, the audio is sent out to both a 3.5mm stereo headphone jack, as well as a 2-pin 0.1" pitch header.

This shield comes populated with all components as shown in the images and schematic; but it does not come with headers installed. We recommend the Arduino R3 Stackable Header Kit.

Features

3.5mm audio out jack

0.1" spaced header for speaker out

microSD card slot

The SparkFun Sound Detector is a small and very easy to use audio sensing board with three different outputs. The Sound Detector not only provides an audio output, but also a binary indication of the presence of sound, and an analog representation of its amplitude. The 3 outputs are simultaneous and independent, so you can use as many or as few as you want at once.

The envelope output allows you to easily read amplitude of sound by simply measuring the analog voltage. Gain can be adjusted with a through-hole resistor, to change the threshold of the binary (gate) output pin as well. Check the hookup guide below for more information about setting gain.

Each of the three output signals is present on the .1" pin-out at the edge of the board. They are active simultaneously. If you aren’t using one in your particular application, simply leave that pin disconnected.

Get Started with the SparkFun Sound Detector Guide