In fact, the only thing that happens here is the lighthouse effect. The faster a pulsar spins, the more it emits electromagnetic radiation one after the other. For example, a pulsar spinning 700 times per second sounds like a sizzle. In fact, what we hear here is not the sound of the pulsar, but the translation of radio waves into sound waves, you can apply this to any wave, in short, these sounds are created by our hands and vary when we convert them into sound according to the frequency of the emitted waves. As I said, this is not the sound of a pulsar, you cannot learn the sound of any object with radio waves (unless it is coded and contains a message by a civilization, for example, the radio waves we use today are coded and contain a message, if you translate this message into sound waves, sound is created, but radio waves in natural conditions do not contain messages, they are just radio waves and they only make noise). Now, you may have thought why I told you all this, so that we could learn something, because it is popularly believed that these are really the sounds of a celestial body. If you convert the radio waves coming from Jupiter into sound waves, you will not hear the sound of Jupiter, you will hear the radio waves coming from Jupiter, but if you want to hear it, all you will hear is the sound of stars and heavy thunderstorms.
