The Gaumont Chronophone is a dual turntable system meant for synchronising film and audio. See, the longest talkie film that could be made at the time was a 200ft roll of film, because gramophones could only play for a limited time. This 1910 DJ system allowed the projectionist to play movies with audio of essentially unlimited length by continually swapping between platters, DJ-style.
The Chronophone used a compressed-air amplifier (!), called the Eglephone, and was loud enough to treat an audience of 4000.
The ramophones, are driven from a common electric motor, and an air hose sends compressed air to each valvebox. There is a control box/valve just under the air pressure guage, presumably to crossfade between the two platters.
Below the control box, there is also a manifold which connects the the gramophone output pipes to the two horns. Quite how the record arms are pivoted so they can follow the track on the disc is a bit unclear, but there appears to be some sort of ball joint where they enter the manifold.
Here’s the Stylus”, with compressed entering, then exiting through two pipes at each side. There is a spring in there to reduce huge downward force.
This thing looks like it would eat records for lunch.