Bassist Krauss, brother of Alison, furthers his fondness for the unclassifiable on his second solo album.  Operating within a basic but broad-minded trio setup that includes guitarist Dean Parks and drummer Matt Chamberlain, II shifts from warm acoustic atmospherics to more progressive ambient experiments that enlist that devil of all guitar innovators, Bill Frisell.  Curiously, though, Krauss himself takes the guitar reins for the album’s chunkiest rocker, Pinky Ring.  The other side of II invites guest vocalists to color the album’s abundant sense of mystery.  Lyle Lovett again shows his noir side in a sly, shadow-filled cover of Tracy Nelson’s (I Could Have Been Your) Best Friend.  But II’s biggest dip into the twilight zone comes when Shawn Colvin helps transform Pink Floyd’s requiem on madness, Shine On You Crazy Diamond, into a reflection of simpler but far darker fancy.  In the light or out of mind, II is one fascinating trip.