This SACD from PentaTone was recorded originally in 1970, not long after he’d made his official debut as an organist. (His organ recitals are notable for being played from memory.) The performances were taken down in the then-new quadraphonic system & released on Philips LPs. But of course quadraphonic LPs were a less than ideal carrier for the 4ch sound on the tapes. Fortunately PentaTone, a company founded by ex-Philips personnel, has been reissuing quad recordings on SACDs remastered from those tapes & they sound spectacularly lifelike. They are, of course, in 4ch sound, not the 6ch that the modern SACD system is capable of.