Some people march to their own drummer. Others, it seems, hum.
With wind chimes and an electric cello as accompaniment, about 50 people stood in a pedestrian tunnel in MacArthur Park on Sunday and, for more than half an hour, hummed.
"This tunnel resonates in the key of E-flat," Harry Gilbert, who played the cello, said. "People sing the notes they feel . . . improvising to make beautiful music."
It was the second annual MacArthur Park hum-along, one of more than 20 such events music teacher Bonnie Barnett has staged over the years here and in San Francisco.
The Independent Composers Assn., a 10-year-old organization promoting new music, sponsored Sunday's hum.
Those participating included musicians, artists and others who were merely curious passers-by.
Previous singing experience was not required.
Barnett said that just about anybody can achieve "acoustic harmony" if he or she hums long enough with a group of people.
"And when you're in tune, you're in tune," Barnett said. "In tune to that group of people and to the environment. And then there's a ripple effect and (participants) carry a good feeling away with them."
Some participants compared the hum-along to yoga, saying it created the same soothing, almost hypnotic feeling of tranquility.
For some, the music emanating from the tunnel and mingling with the sound of the wind chimes was choir-like.
But other park visitors, who had not known about the hum-along, looked at the group with bemused curiosity.
"What are they doing? Are they praying?" construction worker Enrique Espindola asked in Spanish.
But he, too, joined the group and later reported: "I concentrated on the sound and felt a nice sensation."