@edzpambid I don't know enough to answer your question, but one of the times I have seen Ken address the covered sound is in this reaction video:

@edzpambid hi, to add to what @iraR mentioned here not all opera singers do covered sound, even thought it is the most common , you can look for Alfredo Kraus and youll see he was REALLY bright not covered, and he was considered one of the greates opera singers of all time


so no covered sound doesnt mean belting register
the belting register and the call register to my understanding are interchangable

and the falseto register when belted is called reinforced falseto which is what we train in KTVA called also head voice, ken has very good info in youtube about this look for his webinars