The NYE TV spectacular was themed as the launch of The Gathering and was fronted by Miriam O'Callaghan, live from College Green in Dublin's city centre.
But Today FM host Ray (48), who sat in to watch the Countdown Concert, has slated the show, describing it as "brutal".
"I watched it, and the sound was terrible," he said.
"RTE have failed so many times in ringing in the New Year, that I thought maybe this was going to be the year. It wasn't. It was brutal."
But despite Ray's criticism, RTE's New Year's Eve coverage still topped the ratings table and was the most watched programme on the night, with an average audience of 583,700 and a reach of 1,307,500.
The event was beamed live into homes around the country, featuring musical interludes and celebrity interviews.