Part of why it feels strange calling The Necks “jazz” is that they’ve always put individual expression second to the dynamic of the group. Collecting four 20-minute improvisations used to open practice sessions, Travel is a great introduction both in its digestibility (typical Necks albums are usually a single track running about an hour long) and in how it captures the band’s peculiar, meditative intensity, which can range from churchlike (“Bloodstream”) to threatening and noir (“Signal”). That the other two tracks draw their names from active verbs—“Forming” and “Imprinting”—tells you where the Australian group’s collective head is at: process, process, process.