Summer and fall seasons collide in a busy slate for weekend music, including the year’s last show at Blue Hills Bank Pavilion and the beginning of the month-long Pipeline! cavalcade of local bands. For starters, Bob Mould hits the Paradise Rock Club with rock band in tow on Friday to exercise his solo catalog as well as tunes from his former band Husker Du, while ex-Mahavishnu drummer Billy Cobham rolls into the Regattabar to celebrate his 1973 solo jazz-fusion landmark Spectrum. There’s also the Chicago Afrobeat Project featuring drummer Tony Allen of Fela Kuti fame laying down the horns and polyrhythmic grooves at Johnny D’s Uptown.

Friday’s also the opening night of Pipeline! at 25 presents: 50 Years of Boston Rock with one of its older entries, the ’60s then-teen psychedelic band Freeborne, plus ’90s major-label rockers O Positive, plus Cordelia’s Day and We Saw the Wolf at Arlington’s Regent Theatre. The reunion-rich series, toasting the anniversary of MIT radio station WMBR’s local music program, continues Saturday at Cuisine en Locale (the old Anthony’s function hall at 156 Highland Ave., Somerville) with the Turbines (“Wah Hey!”), the Neats’ Eric Martin, the Dogmatics and others. Here’s the rundown.

On the middle of the road side, tunesmith Jason Mraz charms the masses in two relatively intimate shows at the Citi Wang Theatre on Friday and Saturday, while Saturday afternoon finds populist rockers O.A.R. join Phillip Phillips and Christina Perri at the free Mixfest 2014 concert at the DCR Hatch Shell on the Esplanade. Or for a guy who sounds and looks smartly retro with a modern edge, I’d recommend R&B rocker Nick Waterhouse’s return to the Brighton Music Hall on Saturday.

Blue Hills Bank Pavilion closes its season Sunday with a hearty if oddly matched trip of groups on the Honda Civic Tour. The frisky, entertaining and danceable Grouplove headline with Pacific Northwest psychedelic pop modernists Portugal. The Man, but get there early for the impressionistic folk-rock big band Typhoon.

Finally, for my Thursday Throwback, with this week’s free iTunes stunt release of U2’s Songs of Innocence, I’m looking back to the band’s last truly revolutionary drop, 1991’s Achtung Baby, and its subsequent concert tour. “I’m ready for what’s next,” Bono sang live in “Zoo Station,” the first several new songs that opened the band’s 1992 shows, coming off dark and playful, eccentric and electrifying. U2’s new surprise album initially yields a string of pleasant, cleanly produced tunes, but nothing that’s instantly memorable like the Achtung Baby stuff. Maybe that’s an unfair yardstick, and Songs of Innocence seems more lyrically engaged than recent efforts, but let’s see the quartet get back on tour to see how it all pans out, whether U2 remains rock giants or has-beens.