Don’t show up late to see fun — the pop music trio that breaks all kind of musical rules — or you’re going to miss Steel Train. That would be a shame, because Steel Train is running on a fast track.

Kinda jammy, kinda classic-rock and kinda alt-country, Steel Train has nevertheless found itself lumped in with its more age-appropriate post-punk and emo counterparts. Sure, the band’s on Drive-Thru ...