I made a circuit based on a diagram from my physics teacher. The circuit has a 555 chip connected to seven wires that make up a circuit. The circuit includes a photocell resistor that acts as a variable resistor. My question is why are capacitors needed to make the speaker work? I'm sorry if this question seems to be a duplicate of What is the job of the capacitor in a 555 circuit?, but the answers on that question don't explain how capacitors help the speaker work.