Verify you have all the components shown here, and prep your solder station and tools.

There are three 150Ω resistors, two 10kΩ resistors, and one 1MΩ resistor. Take special care to identify that your resistors are correct as shown, so that you know where to place them on the board.

Pre-bend your resistors to right angles as shown. This will make them easier to insert when soldering.

Insert the resistors into the board as shown, using the marking on the board to confirm which resistor goes where. The orientation is not important.

Flip the board to the underside and solder the resistors. You can bend the legs outward to ensure they remain in place while upside down. Repeat this process for the remaining components.

Use wire cutters to trim down to the solder joint. Repeat this process for the remaining components.

When installing the three LEDs, the short leg must go into the white marking as shown. Pay close attention when inserting, then flip and solder.

The x4 transistors are installed near the bottom of the board. The orientation is critical, so be sure to line up the curved edge with the curved markings on the board, as shown. The flat edges should be facing to the right.

The capacitor fits in to the left of the transistors as shown. The orientation does not matter.

This is the component that will react to your sound input. The circular marking on the board should line up with the orientation. Double check to make sure the orientation is correct, then flip and solder.

The switch should be oriented to face outward as shown. When installing, be careful to use as little heat as possible since the switch can melt somewhat easily.

Flip the board to the underside and install the battery connector in this orientation as shown. Be careful not to install it backwards!

Plug in a 9-volt battery to the other end of the connector, and you're done! Thank you for building!