In the next section we'll finally start using the oscilloscope to look at audio signals.

Before we can do that, we have to connect audio jacks and the necessary wire connections to our breadboard, so we can get audio signals onto our breadboard, alter the sounds with circuits, and output the sound to a speaker or headphones, while also being able to analyze our circuit with the oscilloscope.

Also before we even get started, please disconnect your battery from your breadboard for this section. Don't wait until the end of this paragraph, just pull it out right now. There's some serious safety issues with having a battery or other power supply close to an audio jack connected to expensive electronics like headphones or a laptop. Those issues are easy to avoid, and easy to understand, but are a topic for later once we get into amplifiers and other powered audio circuits.

(Correction: at 1:45 I say "jack" when I mean "cable".)

In the video below I say you'll need two aux cables, but if you're listening on headphones, you'll obviously only need one.

If you really want to know about the safety issues - I didn't have time to record a video about this, but I should add one. Basically, if you accidentally connect the positive end of your battery into the headphone jack of your laptop, or a pair of headphones, or another speaker, it can damage or even destroy them. None of these things were made to have 9 volts DC plugged into them!