Jazz and vocal fans have a lot of reasons to send their thanks to Japan. That island has kept excellent artists such as Carol Sloane recording while America embraces the latest disposable pop act. Sloane has always recorded with a who's-who of jazz musicians and, much like Abbey Lincoln or Rosemary Clooney, age has only strengthened her interpretive gifts. Sloane's career started out strong in the late 1950s before it was sidelined by the coming of rock and the youth market. She re-emerged bigger than ever in the '70s. While her early albums are good (the cool, swinging Out of the Blue (1961) has been rereleased on Koch), her small group jazz recordings on the Concord label are even better.