as i'm assuming you use German based on your screenshots, Deutsch ins ()
Tools>Options>Library & Folders (Extras > Optionen > Bibliothek & Importieren)
Manage Library Fields... (Bibliotheksfelder verwalten...)
Add New Field (Neues Feld)
give your new tag a title (i call mine "Resolution"), and choose
DataType: String (Datenformat: Zeichenfolge)
Relational: Store one value for each Album (Verbindung: Speichert einen Wert fur jedes Album)
check the button Calculated Data ("Berechnete Daten"). In the box labelled Expression (Ausdruck), copypasta this:
ifelse(isequal([Bit Depth],16,4),[File Type] - CD, isequal([Bit Depth],16,5),[File Type] - HD)
now you have a tag, that will say FLAC-CD for CD quality, and FLAC-HD for higher quality. you can make it say anything you want, or change colour or whatever. In any view, you can sort using this option instead of [File Type] ([Dateitypen])
we are all allowed (of course) to do whatever we want with our own collections, but i have to say it's completely silly to not leverage the power of metadata in a digital collection. make all the tags you could ever use and you'll be happier for it.