"PORTRAIT OF JOHN WILLIAMS": pieces by Lauro, Clare, Tarrega, Bach, Vivaldi, Brouwer and others. John Williams, guitar. CBS Masterworks MK 37791 (compact disc); "ECHOES OF LONDON": pieces by Byrd, Purcell, Clare, Elgar, Gershwin and others. Williams, guitar. CBS Masterworks MK 42119 (compact disc). Few instruments reproduce on CD as realistically as the guitar. "Portrait" is Williams' updating of some of his favorite pieces and includes a spirited reading of Vivaldi's Concerto in D as well as an unexpected "Fool on the Hill" by McCartney/Lennon arranged by the Cuban composer-guitarist Leo Brouwer. Williams plays both guitars on several selections. "Echoes" offers one side of superb solo Williams showing off nimble fingers. The second side adds orchestral arrangements by Steve Gray that are so heavy-handed and stilted that they almost overwhelm Williams' playing.