These three files are the kind of master the archive keeps for a scanned sheet or a proof set. Each is offered whole, as it sits on the shelf, so the file you download is the file we would check at the intake desk. Open them in a full-colour editor and read them at 100 per cent before drawing any conclusion about the tone.
The tonal wedge is the quickest check. Its steps should look even from one side to the other, and a band that jumps or sags points to a curve in the workflow rather than to the scan. The plate grain sheet is for fine tone: a soft area with no hard edge will show banding if the output device is short of steps. The proof set is for the page as a whole, from the first sheet to the last.
All three files are larger than most email attachments and are best fetched over a wired or home connection. Keep them together in one folder if you compare them, since they were chosen to be read side by side.