Before microphones were invented, here is a silent film showing how it was done. "Sing into a can!" Other than the recording technique and the material used for the actual record, the processing is the same as today. Not much has changed in a century. And yes, I understand the irony of a silent movie on making recordings, but you can see a good example of a wax disk/cutter, etc. Rare film and surprisingly accurate. Behind the scenes at the Columbia Grafonola co. However, just two years later, the recording industry changed over to electric recording, Victor and Columbia had the Western Electric process in 1925, the smaller companies had to wait until 1927 for microphones and related gear to be installed. That's why some recordings (like Louis Armstrong's Hot Five, etc.) recorded in 1926 are still acoustic, no rights to the electric process yet. Typical.