Holly Humberstone, courtesy Constantine Spence. This week’s new music roundup includes lo-fi rock from zzzahara, intimate jazz from Alabaster DePlume, hip-hop/R&B-fusion from TOBi, alt-rock from Holly Humberstone, alt-pop from Babebee and a soulful ballad from Gareth Donkin. zzzahara, “Kensington” — Named after their favorite street in Angelino Heights, L.A.…