I've got a good understanding of basic "rhythm", so I thought I'd take the next step and bought Jan Rivera's "Advanced Rhythmic Concepts for Guitar" (hardcore polyrhythm & polymeter). It's a bit too big of a jump. Any suggestions for an "Advanced Beginner" text? Where I'm trying to go beyond is the basic 1,2,3,4 ... 1,2,3,4 single note runs w/ with ocational double-stop, syncopation, etc. I guess what I'm thinking is that drumming can be entertaining even though it's basically atonal. I'm tempted to just get a basic Tenor Quad/Quint, bass + tenor or tympani drum sheets and "assign" each drumhead to a string.