Tomorrow evening, the performers are Steve Roach and Darren Kearns. Roach was a founding member of one of the first synthesizer-dominated new-music groups, Moebius; local musician Kearns plays the guitar as his primary instrument while frequently collaborating with synthesizers.
Trans-Sonic: A Festival of New Music, at Harrison Auditorium, University Museum, 33d and Spruce Streets, at 8 tonight and tomorrow night. Tickets: $10. Information: 483-7888.
Heavy-metal acts Judas Priest and Dokken will perform at the Spectrum on Sunday evening. Judas Priest, whose new album is Turbo (Columbia), is the old- pro act on the bill; it has settled into a comfortable routine of huffy vocals, menacing lyrics and loud guitar chords. Dokken is a younger and cuter band than Judas Priest; having just released Big and Beautiful (Elektra), Dokken is a band of upstarts hoping to achieve the sort of success that Van Halen has acquired by appealing to the vast mainstream audience that lifts a heavy-metal act out of the confines of its genre.
Judas Priest and Dokken, at the Spectrum, at 7:30 p.m. Sunday. Tickets: $14.50 and $12.50. Information: 389-5000.
The Idle Rich is a local sextet that neatly avoids the staid artiness of so much of the English post-punk music to which it owes much of its style. The band accomplishes this by keeping its tempos brisk and its melodies spare, and the Idle Rich's recent three-song cassette tape is a moody, well-played pleasure.
The Idle Rich, at the Kennel Club, 1215 Walnut St., at 11:30 tonight. Tickets: $6. Information: 592-7650.
What is being billed as an "all-ages, no-liquor, matinee" rock show will be held at the Kennel Club on Sunday. The local bands featured are the Dead Milkmen, rapidly becoming one of the most popular acts on the Philadelphia scene and soon to release a new album, and King of Siam and Tons of Nuns.
The Dead Milkmen, at the Kennel Club, 1215 Walnut St., 5 to 10 p.m. Sunday. Tickets: $5.50. Information: 735-6590 or 592-7650.