Mr. McCarthy, 62, died from complications caused by myelo-dysplastic syndrome, a deadly blood ailment that forced him from his morning drive-time news and talk show in late July.
A member of the Radio Hall of Fame and 1994 recipient of the Marconi Award for career achievement, Mr. McCarthy also performed radio voice-overs for a number of advertisers such as General Motors Corp.'s Chevrolet, Chrysler Corp.'s Dodge and Kelly Services.
"He had a conversational, one-on-one voice that came out very believable," said Craig MacGowan, senior VP-director of broadcast production at Dodge agency BBDO Worldwide, Southfield, Mich.
Mr. MacGowan, like a number of Detroit ad people, counted Mr. McCarthy as both a professional associate and a personal friend.
"It's going to be very difficult for WJR to replace him," said Dick O'Connor, chairman-CEO of Campbell-Ewald, Warren, whose clients such as Chevrolet, Delta Faucet Corp., Amoco Corp. and GMAC, have advertised on Mr. McCarthy's program.
However, Mr. O'Connor said clients probably won't revise radio schedules until they see how WJR's ratings hold.
"It was the best audience you could get in Detroit," he said. "We'll continue to recommend that show until we can look at the" ratings.
WJR, owned by Capital Cities/ABC, was the top station in Detroit last year, with $18.4 million in revenue, well ahead of No. 2 WKQI-FM at $13.5 million, according to Duncan's Radio Market Guide, Indianapolis.
Because Mr. McCarthy's audience was both broad and influential, advertisers paid a premium or agreed to buy time on other station programming to get on his show.
Mr. McCarthy generated 40% of the station's revenue, said James Duncan Jr., publisher of the Duncan report. WJR also relies heavily on sports properties such as the Detroit Tigers, Detroit Red Wings and University of Michigan football and basketball.
Mr. McCarthy was renowned for pulling in top newsmakers and sports personalities for interviews.
"It's still a great radio station," said Fred Yaffe, chairman-CEO of Yaffe & Co., Southfield, citing WJR's large coverage area, loyal audience and ability to deliver news and sports programs.
Currently, veteran WJR announcer Jimmy Barrett has been filling in on the morning program, and the station hasn't announced a permanent replacement.
WJR executives weren't available to comment on plans, but some local observers believe they're assessing whether to largely continue Mr. McCarthy's format or institute bigger changes to reach younger listeners.