Do you like to experiment with audio circuits? This product takes audio input and plays it through a speaker. As a part of this process, it also processes the inputs so that they can easily be sampled with the ADC of a microcontroller.

In the most typical use case, you need to hear what your circuit is doing but the signals are too faint to drive a speaker - maybe it is the output of the DAC of your microcontroller, or the signal coming from your laser beam audio transmission system. This product helps you with that - you just connect your signal to the 3.5mm jack (or a pin header) and supply power. This product takes care of the rest with its amplifier circuitry and an onboard speaker. You can control the volume with a slide potentiometer so that you do not need to search for a screwdriver. This way you can focus on your actual project instead of wiring up some sort of an amplifier circuit every time!

Sometimes you want to listen to the signal and have it processed somewhere else. For those use cases, there is an additional audio jack in parallel with the input.

In another type of a project, you might want to sample audio using a microcontroller. Usual line level signals have a voltage range of about -0.5 to 0.5 volts. However, the ADCs of microcontrollers often require that the input voltage is between 0 - 3.3 volts. This product takes care of the voltage level conversion and sums the stereo channels together to create a mono signal to reduce the computational load on the processor. This microcontroller-friendly signal is available on a pin header which is conveniently near to an on-PCB breadboard. You can use this functionality simultaneously with the speaker circuit.

To sum it up, this product has a daisy-chainable input which is connected to a level-shifting stereo-to-mono amplifier. The output of the amplifier can then be connected to some external circuitry (on the breadboard for example) and/or connect it to the onboard class D amplifier which has a slide potentiometer for volume control. The output of the amplifier drives an 8-ohm speaker which is mounted on standoffs.

Due to shipping weight, the product does not come with the mint tin. However, you do not need to cut any holes into the tin as all the connectors are designed to be used with the lid open. The kit comes with all the surface mount components soldered on the PCB. The through hole parts are supplied in a bag for you to solder.