Music: Bach at the Barricades

MUSICnBach at thenBarricadesnby Dale Volberg ReednReprise: The Extraordinary Revivalnof Early Music by Joel Cohen andnHerb Snitzer, Boston and New York:nLittle, Brown; $25.00.nIn the Middle Ages and Renaissance,nas far as 1 can tell, people played onlyncontemporary music. Since then, itnseems, there has been a completenturnaround, and only . . .