I was very excited to discover the new option Convert Tag-Tag, but I can't figure out how to make it do what I want, which is to split one tag field into two, given the delimiter.

The the first example, the existing Title field contains the actual artist and title separated by "/", e.g.
Art Porter / Nevermore
Simon & Garfunkel / Sound of Silence
Santana / Smooth
I want to split these tags into the real Artist and Title tags.

In the second example, the existing Title field contains the actual composer and title, d.g.
Beethoven / Moonlight Sonata
J.S. Bach / Jesus Joy of Man's Desiring
I want to split these tags into the real Composer and Title tags

Can anyone show me what to put into the Tag-Tag command dialog to achieve these?

- Rich

I haven't used the new converter yet, but wouldn't it just be

Field: TITLE
Format string: %artist% / %title%

and

Field: TITLE
Format string: %composer% / %title%

To answer my own question... No, that doesn't work.

The Tag - Tag converter isn't as intuitive as I would have thought. The 'Field' is the target, not the source, so apparently you can't do what you want with the converter.

What you want to use instead is a 'Guess values' quick action.

Source format: %title%
Guessing pattern: %artist% / %title%

Yes, the Tag-Tag Converter is a quick version of the Format Value action, not of Guess Values. You can write only one tag field with it.

You can do your field splitting with the Tag-Tag Converter, but it needs two steps:

Step1:
Field: ARTIST (or COMPOSER for example two)
Formatstring: $regexp(%title%, / .+,)

Step2:
Field: TITLE
Formatstring: $regexp(%title%,.+ / ,)

Thank you, pone. In Step 2, can the Title safely depend on itself?

I don't understand what you mean with that?

Step 2 deletes everything before the dash, including the das and the following space, from the title field.
You have to make sure that there is no dash which is part of the actual title or artist name.

well here we have a common problem. A very powerful program, but sooo hard to use! I too have been trying to replace the field TITLE with a very simple replacement, but have been boggled! The Title of a few files has extra numbers before the text, e.g. "04 Hide not", and I wanted to change them to delete the preceding numbers, i.e. to delete 04 for this file, but so too for all the files.
So now I downloaded the new edition of mp3tag, and hey presto, it has a new function (which should have been there all the way), Convert tag - tag!! So I try to change the title this way, but it won't work in any way!! Why can't we have a really simple dialog, Tag - Tag, where we could choose the field in the first box, i.e. Title, then choose in the second box the pattern, i.e. %1 %2, then in the third box I would type %dummy% %2!! So simple!
There are so many people asking questions all because there are no simple precedures to employ! Everything is so complicated!
I finally managed to track down the way to do it in Actions quick, replace with regular expression, but had to use such funny scripts, like (.2) and $2, I didn't really know hat I was doing. But if we already have such simple ideas like "%1 %2" to change to "%dummy% %2" in filename to filename, why not employ this globally??
Hoping to hear from you soon!

What I meant was, the new value of the title field is calculated from its old value. For this to work correctly, without creating a circular definition, the new value must be completely calculated from the old value before it is stored, overwriting the old value.

This is how Mp3tag works and this works savely.

So any reply from the crew why they can't simplify the Tag-Tag converter? Why can't we use placeholders? (%title%, %1 %2) That would simplify matters greatly!

Why would you want to use two 'converters' instead of a single action? The quick actions are essentially one-off converters.