"They come to enjoy the jazz festival," said Mr Herrmann.
He accused Mr Lunt of shooting from the hip without any knowledge of the 50th anniversary programme, most of which would be announced early next month.
Mr Herrmann said Earth Wind & Fire were bigger than Meat Loaf and the festival was getting the band's only concert in New Zealand. It had headlined at other leading jazz festivals around the world.
"Jazz festivals have to be nimble and relevant to survive."
Mr Herrmann said the core of the festival remained jazz but around it were other musical styles that had links to the jazz genre.
"Colin does not appreciate what we are trying to achieve ... the depth of jazz music in the core of the festival is huge, absolutely huge," he said.
Mr Lunt said he was not saying that the festival should only cater for the jazz purist. "It has always catered for a wide cross-section of music, but there is a limit."
It was a cynical approach to get more people to the festival after this year's thumping loss, he said.
Mr Lunt, who now lives in Auckland, believed that part of the reason the festival was struggling was the rising cost of tickets so that people on tight budgets were unable to take in as many shows.
"The festival has to be profitable but not at the loss of the quality and integrity of the music, in particular the New Zealand content." Mr Herrmann said the programme would include several high-quality international jazz musicians in the main concert series and a gala concert celebrating the history of the festival, with musicians who performed during the 1960s and 1970s as special guests.
"The concert is for the wider community who have carried the jazz festival over many decades."
He said Mr Lunt did not know what was going on behind the scenes and not a single member of the festival committee objected to Earth Wind & Fire.