Hi, I wanted to ask if the speed of a sound wave, given a fixed medium, depends on the speed of the observer. That is to say, does the speed of sound obey to the laws of relative motion, implying addition of relative speeds? In case it doesn't depend on relative motion, can you explain why? I know that the Doppler effect accounts for the speed of the observer, but it only affects the frequency of the wave, not its speed. Why is it so (in case it actually is)? Thanks.