Klezmer Susan Watts, known for her great delicacy on trumpet and Yiddish scatting, is again breaking new ground, thanks to a grant from the Community Partners program of the American Composers Forum to write new klezmer music in the Philly style. The community part means there is a group of enthusiastic amateurs, well-rehearsed and joining the Shpielkehs in this grand debut.

—Mary Armstrong

Sun., April 23, 4 p.m., $7-$17, International House, 3701 Chestnut St., 215-729-1028, www.crossroads.calvary-center.org.

It's a big weekend for new music—as in, so new it hasn't been heard before in public. Orchestra 2001 is throwing a mini new-music festival that will include four world premieres by Jay Reise, Thomas Whitman, Jordan Nelson and Larry Nelson. Reise gets the prize for prolificness, with another new work presented by the Network for New Music on Sunday. Network will also present new commissions from Steve Mackey and Jan Krzywicki. Don't miss any of it.

—Peter Burwasser

Orchestra 2001, Sat., April 22, 8 p.m., Trinity Center, 22nd and Spruce sts. Also in Swarthmore, April 23. 215-922-2190. Network for New Music, Sun., April 23, 3 p.m., Settlement Music School, 416 Queen St., 215-320-2600, www.networkfornewmusic.org.

Legacy big bands are a dime a dozen and so-called "all-star" bands rarely live up to the billing. But Dizzy Gillespie instigated so many careers over his six decades in music that there's no need to assemble a bunch of hacks to stumble through "Salt Peanuts" night after night. With names like Jimmy Heath, Randy Brecker, Monty Alexander and James Moody involved, the wit and fire of Dizzy's songbook should be lovingly served.

—Shaun Brady

Fri., April 21, 8 p.m., $27-$71, Verizon Hall, Kimmel Center, 300 S. Broad St., 215-893-1999, www.kimmelcenter.org.

Aiden James—featured earlier this month on the cover of the regional LGBT mag Visions—knows all about the power of word-of-mouth buzz. That's why the honey-voiced twentysomething has established what he hopes will be a regular concert concept called Voices to Be Heard: showcasing not only his own insightful folk-pop numbers, but those of like-minded area talents whose energy he digs. Be on time to catch the rich, shades-of-Joan-Armatrading vocals of musical vet Lili Anell.

—Nicole Pensiero

Sat., April 22, 7 p.m., $5, with Arlene Mccann, Ron Morris and Lili Anel, Pontiac Grille, 304 South St., 215-925-4053, www.aidenjamesmusic.com.

These excellent young bands are diametrically opposed in their approach to acoustic, string-based music. The Wiyos thrill with their resurrection of old jugband and Tin Pan Alley material, accompanied by virtuosic fingerpicked acoustic guitar and a comedian on the bass. The Mammals are rooted in the Appalachian stringband trad with urban social consciousness. Their new CD, Departures (Signature Sounds), cues fans with the title: away from the overtly political and old-time to vaguer lyrics and more rock sound.

—Mary Armstrong

Fri., April 21, 8:30 p.m., $13, Tin Angel, 20 S. Second St., 215-928-0770, www.tinangel.com.

The quintessential songwriter's songwriter, Brown has had his often-aching songs covered by everyone from Carlos Santana to Willie Nelson. Brown even had a tribute album, 2002's word-of-mouth favorite Going Driftless (with guests that included alt-country angels like Lucinda Williams and more quirky talents like Ani DiFranco). Seems everyone loves his songs, but no one can put quite the spin on them that the picker-poet himself can.

—Nicole Pensiero

Sat., April 22, 7:30 p.m., $33-$38, World Café Live, 3025 Walnut St., 215-222-1400, www.worldcafelive.com.

Percussionist-turned-composer Matthias Kaul says he wrote his recent piece, "Arabesken," to "remind the listener that in all discussions about Arabian cultures we tend to forget that we successfully integrated lots of Arabian influences in our culture." Gene Coleman's Soundfield series has been all about integrating cultures and technologies, with international electro-acoustic musicians in often compelling combinations. Ensemble Noamnesia will perform "Arabesken" as well as pieces by Coleman and John Cage.

—Shaun Brady

Wed., April 26, 8 p.m., $10, Slought Foundation, 4017 Walnut St., 215-222-9050, www.slought.org.