Hartwood Amphitheater on Middle Road in Hampton Township will be the site of the 10th Annual Allegheny County Musical Festival, featuring Rusted Root, beginning at 7 p.m. Sunday. A $20 per car donation will benefit the Department of Human Services. Call 412-767-9200 or 412-350-2478.

<B>Waterloo,</B> the ABBA Swedish tribute band, will appear in "ABBA, The Music" at 7:30 p.m. Wednesday at the Benedum Center, 719 Liberty Ave., as presented by the Pittsburgh Cultural Trust. Tickets range from $34.50 to $39.50. Call 412-456-6666 or visit pgharts.org.<B>JazzLive</B> from 5 to 7 p.m. Tuesday in Agnes R. Katz Plaza, diagonal from the Benedum Center, 719 Liberty Ave., concludes with a JazzLive Jam Session with Roger Humphries this coming Tuesday. In case of inclement weather, JazzLive will move indoors to the Cabaret at Theater Square, 655 Penn Ave. Call 412-456-6666 or visit the Web site, www.pgharts.org.