The Magic Circus, a rock ballroom which plans to present a summer-long series of concerts in "exciting sensory environment," will launch tomorrow at the Hollywood Palladium.

Headlining the opening bill are The Who, Poco, and the Bonzo Dog Band in continuous performance from 8 p.m. to 2 a.m.

Tentatively scheduled to appear at later dates are Johnny Winter, The Chambers Brothers, Spirit, Canned Heat, John Mayall, The Al Kooper Show, Joe Cocker, Delaney & Bonnie & Friends, P.G. & E., Ike & Tina Turner, Charles Lloyd and Sweetwater.

The Who, a top English rock band, is to debut its rock opera "Tommy," which earned a gold record two weeks after its release. Led by guitarist-writer Peter Townshend, the Who is regarded as one of the more creative and visually exciting acts in the field.

Ballroom sound system was especially designed for the facility by Hanley Sound of Boston who has also designed systems for Fillmore East, the Newport Jazz Festival, the Miami Pop Festival and ceremonies for President Lyndon Johnson, according to Circus management.

A "clear light" device will key the ballroom's environment. It is a departure from the light show concept that will be seen for the first time at tomorrow's opening.