Easiest way to bulk update just one ID3 tag value

Mac
1

If I wanted to update all of the files currently in MP3 to change just one tag to a specific value (which will always be the same), what is the easiest way to do that?

I basically want to have the same comment added ("Vinyl Recording") in all files, but for every other tag to remain.

Thanks

2

Select all files.
Enter the text in the tag panel in the comment field and save the modification.

3

Ah, sorry, I know I could do that, but I am trying to automate a little more, so I was thinking something along the lines of an action, and the value is hard-coded in that action so I don't have to type it, and can be sure that it's consistently applied.

4

You still have to select the files.

Create an action of the type "Format tag field" for COMMENT
Format string: Vinyl Recording

5

I looked at this and completely mis-read what was meant by 'Format', didn't realise it was to apply/add tags (and how to format it). Makes sense. Thanks