Check out YouTube for clips of Michael Manring, esp. "The Enormous Room" and "Selene" - astonishing use of D-tuners (and alternate tunings AND a de-tunable bridge) on all 4 strings of his Hyperbass!!
Also check out "Excuse Me, Mr. Manring": he uses standard EADG tuning, flipping the D-tuner on his E-string to get a low B, down & back again.
Truly, the King of D-Tuning!!
