Leave it to Dick Hyman to conceive of If Bix Played Gershwin (Arbors), a superior example of imaginative jazz repertory. This extraordinary chameleon of a pianist and compendium of jazz styles teams with cornetist Tom Pletcher and a host of pre-Swing Era enthusiasts including bass saxophonist Vince Giordano and Dan Levinson (on various reeds) to filter the music of composer George Gershwin through the sensibility of Bix Beiderbecke, the immortal brass man who brought a new, reflective lyricism to jazz in the 1920s. Hyman may be the brains behind the project (and the arrangements) but he immerses himself selflessly in the ensemble conception, stepping out for a solo feature on “In a Mist,” a Beiderbecke tune ingeniously infused with melodic strands of eight Gershwin pieces. Beiderbecke, it seems, never recorded a George Gershwin melody; this scrupulously idiomatic yet robust project brilliantly conjures up that which never was. As fantasy projects go, it’s simply a dream.