When pairing and unpairing my headphones, I noticed that it plays a little jingle that ends on a high note when paired and a low note when unpaired. It seems natural at this point that a higher note at the end would indicate a connection because I have been using them for so long but it makes me wonder if that would have always been the case. I don’t know much about music and chord progressions but I would think that a higher note ending would convey happiness consistent with how the manufacturer wants you to feel when you use their products, and a lower note ending would convey sadness or some type of negative motion for stopping use of their product.
On the topic of pairing noises, I noticed the sound another speaker makes when in paring mode resembles a radar blip which is a cool experience to give the user. I think the sound adds a layer to the experience of pairing a device by tying it to searching for non-visible objects.