A new kol koreh came out against the Lipa concert. the names of Rav Shuel Kaminetzky and Rav Dovid Feinstein are not on it. An article from elsewhere about it:
This year, like last, there were some people who wished to stop the efforts of the concert organizers and performers. (the website) has discovered that virtually every single Litvishe rosh yeshiva refused this year to sign any letter or kol koreh banning a specific singer or The Event concert.
Gedolim have faced tremendous pressure from certain so-called activists and have maintained their position despite fabricated stories that all other roshei yeshiva would be signing against concerts and/or singers.
One particular rosh yeshiva whom (website this was swiped from).com was in contact with mentioned that these activists sat with him for over an hour, not willing to let up, and telling him that they have signatures from every other rosh yeshiva. This particular rosh yeshiva had the foresight to pick up a phone and contact a few other roshei yeshiva only to find out that they too were told the same stories but refused to sign.
Of course, at the same time, these rabbonim have said that it is vital to reinforce the idea that concerts should be comprised of kosher entertainment that does not contradict the spirit of the Torah.