The amplifier that I choose to work with these speakers comes from Adafruit, and it comes disassembled. However, the assembly is very simple with access to a soldering iron.
Start by placing the capacitor into the spot shown below. Make sure to put the longer leg of the capacitor into the positive marked hole, as this is crucial to how the capacitor operates. Bend the lead against the PCB and solder the leads to the board. Be careful not to burn the board too much with your soldering iron. Once the leads are soldered, clip the remaining pieces of the legs down to a reasonable size.
Next, place the two speaker terminal blocks into their respective spots at the end of the board (shown below). Make sure that the metal side of the terminal block is facing away from the board. Use some tape to keep these blocks in place, and solder the 4 leads onto the board. There is no need to clip the ends of the leads here.
Finally, we need to setup the amplifier for analog control. To do this, we first need to solder the connections on the board labeled “AD1”, “AD2”, and “Analog” (as shown below, left side). Make sure that the solder fully bridges these connections. Next, solder in the potentiometer included with the amplifier. This is placed in the corner of the board as shown below (right side). It is best to solder the side labeled 3 on the pot to the hole labeled 3 on the board, however this is not necessary if the sizing does not allow it. Once this is in place and soldered, the leads can be clipped slightly.
After testing out the circuits listed in this tutorial, I realized that the amplifier I chose for this project filters out the low frequencies used to light up the LEDs. In order to fix this, we must solder onto the amplifier the terminal block with three inputs, as shown above (left). This is soldered right next to the audio jack input, and allows us to use the input straight from the audio jack to pulse our LEDs with the extra circuit that we create for the LEDs to operate at lower volumes. Solder this terminal block on just as the others in this tutorial.
Now you are ready to test the amplifier! Refer to the testing page for more info on this process.