by William Ruhlmann 　　The Blues Brothers began as an affectionate joke-cum-tribute to R&B music, and taken in that spirit it retained its entertainment value, even after this live album topped the charts, sold two million copies, and produced hit singles in "Rubber Biscuit" and "Soul Man." The guardians of popular music have always been entirely too reverent and humorless, however, and it wasn't long before they were leveling charges of rip-off against the Brothers and complaining that John Belushi couldn't sing as well as Otis Redding. So what? No one seems to have noticed that Belushi was as obsessive about citing his sources as Frank Sinatra is about naming his arrangers -- you'd have thought those critics would have appreciated the footnotes. The beneficiaries of Belushi's encomiums didn't mind the increased exposure or the renewed royalty checks ("I suggest you buy as many blues albums as you can," Belushi told the audience), and even today, what comes across in these performances is the sincerity of feeling -- that and some tasty playing from a top-notch band.