Answer:
Microphone
Explanation:
A microphone is a device that amplifies the sound. It takes in sound signals and converts the sound to electrical signals. These electric signals are then amplified and converted to sound waves once again, but now amplified (louder sound).
MP3 player reproduces the sound, which is already recorded. It is a modern device. Gramophone and Phonograph are also sound reproducing devices. These were famous in the previous centuries. Another name to Phonograph is a gramophone.