Three hours before showtime, Brian Wilson says: "There is no Rhonda."

Sitting backstage, gathering strength for the evening's 48-song, 150-minute concert, Wilson was not asked about her; he just volunteered this fact. The other members of the Beach Boys seem mildly surprised to learn that the 1965 song "Help Me, Rhonda" was about no one in particular.

Not that it matters; the sound is everything. Attention must be paid to baby boomer music-cued nostalgia, and no one pays it better than the Beach Boys. They are currently on a 50th-anniversary tour that has more than 60 concerts scheduled and others still being booked. Their new album, "That's Why God Made the Radio," debuted at No. 3 in Billboard's listing, and with this the Beach Boys topped the Beatles for most weeks on Billboard's top-10 album chart.