I have compared the leteris edition (for get the spelling) with other editions of the Hebrew text that I have - and with respect to the music, it is different.
Psalm 150:2 Letteris: הַ֭לְלוּהוּ בִגְבֽוּרֹתָ֑יו הַ֝לְל֗וּהוּ כְּרֹ֣ב גֻּדְלֽוֹ
Psalm 150:2 others: הַֽלְל֥וּהוּ בִגְבֽוּרֹתָ֑יו הַֽ֝לְל֗וּהוּ כְּרֹ֣ב גֻּדְלֽוֹ׃
How then can one tell which markings to use? The punctuation and melodic inferences in the markings are a highly compact system with little or no redundancy. That makes them highly subject to being miscopied. That will give me something to do over the next 7 years.
What should a volume on music contain - text, cd, examples of musical reception history, various forms of chanting over the last 20 centuries???
For now - my usual random research methods...