If you're looking to label this music as one sort or another--classical, jazz, bluegrass--you're bound to get into trouble. The two Quartets at work here--the Turtle Island String Quartet and the Ying Quartet--are innovators, blending absolutely classical training with a love of experimentation, improvisation, and an ear for unusual textures. The CD begins with a cool, swinging, true jazz classic ("Yearnin'") for the full octet and ends with a version of John Lennon's "Because" which captures the piece's melancholy in just the right manner. Along the way, an original work by the Turtle Island cellist, "Julie-O," discovers the darker and more virtuosic reaches of the pair of cellos. Darius Milhaud's "La Creation du Monde," a 1923 piece that explored the combination of European classical music and jazz, gets a new arrangement, and another original piece, "Variations on an Unoriginal Theme," pits one quartet against the other in a friendly competition that touches on R&B and Samba. This is a unique CD--entertaining and original. --Robert Levine