Question: what is the difference between 16 ohm and 32 ohms?
Answer: 16 Ohm means less resistance than 32 Ohm, so all other things being equal, 16 Ohm headphones can sound louder, but also place bigger strain on the amp as the amp will now be delivering more current. Depending on the amp, this may result in audible distortion if the amp can't handle such high current.