Twenty years ago, Jon Spencer transitioned from Pussy Galoreâs scum-encrusted noise rock to the Blues Explosionâs âElvis with dynamite up his assâ approach. These sophisticated New Yorkersâincluding guitarist Judah Bauer and drummer Russell Siminsâappropriated white-trash demeanors while playing savage, jagged rockabilly and barbed-wired blues rock. Some thought it corny while others found it to be a brilliant twist on hoary musical tropes. Bottom line: JSBX scorch live. If they draw heavily from their â90s albums tonight, expect memorable sparks. (Neumos, 925 E Pike St, www.neumos.com, 8 pm, $20 adv, 21+)