Nope, you are cutting on a blank nitrocellulose coating on an aluminium disk with the audio being sourced (traditionally) from tape.
The audio delay was from the two tape heads and the controls were peak hold and dump with transistor and diode circuitry and capacitors as the memory elements. At 33 1/3rd RPM the disk does one rev every 1.8 seconds, so hold time was only in the order of a second, not too bad with a low leakage cap.
Matrixing for L+R and L-R was done with transformers, and the rest of the computer was transistors and diodes, the nearest thing to a digital bit was the sample and hold state logic (Two transistor bistables) and the PWM generator that controlled the leadscrew rate. The diagrams of the VMS 66 and 74 are out there if you search for em.
Plenty of machines were retrofitted with things much closer to modern computers for control over the years, but you were asking about the 60's tech.
Bear in mind that back then there was HUGE money in this, making records was giving hollywood a run for the consumer disposable income, so complex and slightly fiddly electronics were acceptable.
Once you have the master disk cut the process of making a series run of records is gloriously mechanical, silver then nickel plate the master disk, electroplate up to a suitable thickness, then peel of the resulting metal foil negative, use it to make a positive, then a series of negatives (number depending on expected run rate, these are your stampers, those go into a record press where a ton or so per square inch of pressure (and steam heat) squash the vinyl into the groove, replace steam with cooling water and around we go.
Larry Bodens 'Basic disk mastering' is interesting and the AES have a two volume compendium of collected papers on disk recording.
I once NEARLY took a job in a major studio complex that included disk mastering rooms so I did a little reading.
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