Great Thunder is the songwriting and home-recording project of Katie Crutchfield (a/k/a Waxahatchee) and Keith Spencer (who plays drums for Waxahatchee and bass for Swearin’ — just two of several punk-spirited bands he’s played in over the years). The couple describe themselves as “a clandestine musical project by brother/sister duo currently residing in Philadelphia, Pennsylvannia,” and last year released a startlingly solid 22-track collection of songs titled Sounds Of Great Thunder, ranging from spaced-out psych-rock downers and bluesy garage-rock, to minimal 30-second guitar-and-voice pop tracks and super fuzzy acoustic ballads. Keith and Katie share vocal duties; on some songs they deadpan together, others feature Crutchfield’s moody pop pipes. This weekend they’ve followed up Sounds with a similarly varied EP, Strange Kicks, set for a cassette tape release with Stupid Bag Records. Check out the lead track “Kees” below and head to Bandcamp to stream the other six; there’s even a bonus-track cover of Mazzy Star’s “Fade Into You,” which they’ve made their own with huge noise-pop guitars and drum machine.