For anyone who's interested, this is an awesome article about the genesis of the term "math rock" and what that label has come to encompass. It's pretty focused on the Nor Cal area, but its still a great read with a couple good videos. The guy from Planets (on a bass with an octave shifter pedal) can shred a bass so hard its not even funny. An Excerpt:
"Like so many other presumptive genre names – emo, prog, hyphy, etc. – “math rock,” does so little to actually explain the mechanics of the music within the genre. As a term, “math rock” came from post-punk and hardcore bands playing around with asymmetric or changing time signatures. Its original usage was somewhat derogatory and reductive, with the playful ambiguity of the word “math” yielding both endearing and annoying responses. Does “math” mean math-themed, as in “This song goes out to Riemann’s Zeta Function,” or does it mean mathematically derived, as in “This song is composed only using All-Interval Rows?” Both are off the mark. Especially considering math and music have very profound and subtle connections stemming from subfields in set theory, group theory, and number theory, the “math” of math rock only referring to a few unexpected time signatures seems particularly narrow.
For better or worse, we’re stuck with “math rock” as the definitive genre term to helpfully explain a musical movement that ranges from bands like June of 44 and Don Caballero to Battles and Tortoise. The unifying musical traits of math rock are numerous and easily identified. Vocals are played down, with many bands being instrumental; guitar and bass often use two-handed tapping techniques; drumming is unexpected and accents and timbres are varied constantly; songs rarely use the verse-chorus-verse structure; rhythmically, pieces will move through multiple time signatures, tempos, or feels; melodically, the music is highly polyphonic, with no one dominant melodic line coming from any one instrument; harmonically, tonal and atonal paradigms (12-tone, set theory, modal) don’t necessarily apply; shit generally be crazy. The laundry list goes on and those listed don’t even begin to capture the complexity of math rock’s general “sound.”"