Ex Hex is looking for a little psychotic reaction. The garage rockers from the nation’s capital keep it gloriously uncomplicated on their 2014 debut album “Rips” on Merge Records. Simple and direct, songs such as the midtempo sing-a-long “How You Got That Girl” and the tight, bouncy jolt of “You Feel Apart” are testaments to the power of the song. There are no long-winded solos and indulgent flights of fancy — Ex Hex shakes, rattles and rolls with a youthful exuberance that is at the heart of all great, pre-Led Zeppelin rock and roll. The group brings its sock hop of sounds to Strange Matter on Wednesday. Dec. 9. Opening are Mac McCaughan and the Non-Believers and the Ar-Kaics from Richmond. Doors open at 8 p.m. Admission is $15. strangematterrva.com.