The recording process begins with the creation of a master tape which is then transfered to an acetate. An acetate looks like a vinyl record, but it is actually a metal plate covered in a layer of acetone. Acetates are much more stiff and more dense than a vinyl record. Also, since they are not made to sell, an acetate usually has a handwritten or typewritten label and a plain sleeve is used to store it.

A machine actually cuts the grooves into the acetate like a lathe. This converts the master tape via electronic impulses into grooves on the record. When you play a record, this same transition takes place in reverse-the grooves are converted back into sound. There is a second hole in the acetate, which is covered up by the label. This second hole is needed to stabilize the record during the cutting process.

After the tracks are cut, the acetate is then scrutinized to see if it sounds close enough to the original recording. If it sounds okay, then the "mother" molds are cast from the acetate. Acetates are the rarest form of any record; sometimes only one exists for a particular recording. Acetates are usually one-sided, with the backside being smooth. They can be played, but they wear out very quickly so this is not advisable. Acetate is fragile and can be cut by a phonograph needle just as it can be cut by the machine which makes them.

When mastering to CD, the Recordable CD (CDR) is used in a similar way to acetates, with the sound being checked from a CDR. In the early days of the CD some dealers sold these CDRs for very high prices and referred to then as "CD Acetates". The ease with which they are forged has killed the market for rare CDRs and the term CD Acetate is no longer widely used.