Sleep Dirt is a cyclical guitar chord sequence that is played with three note voicings using a static note, the open D string, being played in every chord chord (except the last one) ... an interesting combination of minimalistic limitations imposed on the progression that produces old fashioned less-is-more greatness ...
Bm9 ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------6-----------6-------------------------6-----------6--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----7------------------------------------7---------------------------------- G#m7b5 (or E7/G#) ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------4-----------4-------------------------4-----------4--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----4------------------------------------4---------------------------------- Bm9 ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------6-----------6-------------------------6-----------6--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----7------------------------------------7---------------------------------- G#m7b5 ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------4-----------4-------------------------4-----------4--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----4------------------------------------4---------------------------------- D/F# Gm ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------2-----------2-------------------------3-----------3--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----2------------------------------------3---------------------------------- D/F# Gm ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------2-----------2-------------------------3-----------3--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----2------------------------------------3---------------------------------- D/F# Gm ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------2-----------3-------------------------3-----------3--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----2------------------------------------3---------------------------------- Fdim ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------1-----------1-------------------------1-----------1--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----1------------------------------------1---------------------------------- Fdim ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ----------------6-----------6-------------------------6-----------6--------- ----------0-----------0----------0--------------0-----------0----------0--- ---------------------------------------------------------------------------- ----7------------------------------------7---------------------------------- Fdim ----------------4-----------4----------------------------------------------- ----------0-----------0----------------------------------------------------- ---------------------------------------------------------------------------- ----3------------------------------------3---------------------------------- ---------------------------------------------------------------------------- ----------------------------------------------------------------------------the choice of chords is interesting in that it is non-functional from a global tonality point of view, i.e. it contains sudden modulations (no ii-V's here, a trademark of Frank's) and serves well to maintaining listener interest almost regardless of duration of piece ...
you can look at the progression as being made up of three sections ... a first Bm/E7 type of doublet thing except the bass is on the third degree of E7 ... but it can also be seen as a Bm9/G#dim doublet thing ... then there's a D/Gm see-saw doublet thing (G melodic minor thing many bands made use of, esp. Max Webster) and then a F dim monotonic teasing buildup ... note that Fdim is equivalent to Bdim ...
... it is seldom you see a tune end on a diminished chord of the same root it is resolving to ... but if you listen to Frank's lines on the last section you'll hear him end is Diminished licks with 1, 2, and b3 on the beginning of the head (Bm9), so the progression lends itself to melodic continuity with a combination of three internal modal noodling zones ... a great composition and recording (nice mics whatever they are !) ... one of the few Zappa two-guitar tunes I can think of ... someone once told me it's Ian Underwood on second guitar, nice job anyway ... when I find the time, I'll score in the remaining chord interlude that comes later in the tune along with some of the melody and solah ..
jc@lynx.bc.ca