"Shame and guilt must go to where they belong: among those who harass and those who protect (the perpetrators)," said a declaration signed by 295 female singers and published by the daily Aftenposten.
In a separate text, 706 female musicians pointed out that "there is no reason to believe that the music community is better here, even in 'the most equal country in the world'."
Norway was ranked the second most gender-equal country in a 2017 World Economic Forum report, which takes into account wage inequalities for women as well as their participation and representation in political and business environments.
Scandinavian countries pride themselves on topping the list in gender equality, with Iceland in first place, Finland in third and Sweden in fifth place.
The denunciations come after the downfall of movie mogul Harvey Weinstein, who has been accused of sexual assault by more than a hundred women.
On the same pages as the manifestos, Aftenposten published several anonymous testimonials from artists who reported sexual violence, pressure and humiliation.
"In Oslo, I was the victim of aggression from someone I had a thing with," one musician wrote.
"I thought like others that this is something common, that it wasn't worth doing something about".
Another singer said that during her career, "I received uninterrupted comments on my looks and my sexuality".
"I had countless text messages from colleagues writing about my looks and nothing about the job I had just done."
The manifestos followed a similar step by more than 500 Norwegian actresses last week.
The Weinstein case also inspired women in Sweden, where nearly 2,000 female musicians have denounced sexual abuse.