Vinyl Lovers everywhere have been riding high on the revival of the Turntable Record Player in which in turn puts the Phono Stages back within the spotlight.
A Phono Stage provides a connection between the record player and amplifier. When vinyl was the standard for audio recording, the phono stage was built-in to receivers and amps allowing direct connection of a turntable.
Hi-Fi Amplifiers now won't let you simply plug in a turnatble directly. You need to connect via a phono stage to make the very small signal from the turntable powerful enough for your main amp to work with.