goody613 – Actually, I was not going to use that to prove my point because the halacha is that shiros ve’tishbachos are not assur. However I saw that the Rambam, when bringing the halacha, says a lashon “ukvar nahagu kol yisroel lomar divrei tishbachos…”, which I think implies that this is new, but originally they were not noheig like that, as you said. Thank you.
cherrybim and wolfishmusings – There’s no way you can know that the songs weren’t written down. How do you think they got all the levi’im musicians to memorize their roles? It would make sense that they had music sheets. They probably just got lost, that’s all. That which wolfishmusings says notational systems did not exist in Dovid’s time is not accurate, in fact there are musical notes preserved from ancient Greece from just about that time.