The ears on dogs can be different sizes and shapes. They can be short and pointed or long and floppy. No matter what size and shape they are, they are very sensitive to sounds. Dogs can hear noises at much higher frequencies and that are four times further away than we can.
They have selective hearing just like you do sometimes. They can sleep through a TV show, but can wake up when a car pulls into the driveway.
Dogs feel vibrations from the earth and are thought to be able to predict earthquakes.