He even seemed to be taking our side. Napoleon and Beethoven, we heard, were the real villains. Before they let loose an uncontrollable spirit of nationalism, people sang properly in German with no trouble. Then there was Fidelio. Lloyd played a disc of the cast bellowing at everyone in sight during the opera's climax. Nothing like it had ever happened before. Singers needed a new dimension of dramatic force to express the rampant energy of the age and the music that embodied it. We were discovering the thin bit of the wedge that ended up with Wagner.
Lloyd lived up to form, cracking jokes about opera born with hairs on its chest and delivering insights born of experience. The macho sound comes not just from the density of consonants, we learnt, but the kind of consonants, and from the uttering of glottal stops before vowels. These effects cause much wear and tear and can make women more macho than the men, to judge by the desperate bawling of a Valkyrie trying to make herself heard from offstage against a gigantic orchestra.
But then the point of view started to get more complex. When Lloyd wanted coaching in the music of Lohengrin, he said, he went to Reginald Goodall, the behind-the-scenes mentor and eventually the preferred front-line conductor of British Wagner performers. Goodall told him that this opera was "Italian muck" and put him on to Parsifal instead. Lloyd told the story with an air of indulgence and made up for it with a dose of Lohengrin sung by Placido Domingo, calling him an honorary Italian. But where do we turn when the Wagnerians turn out to be even more bigoted than we are?
Riding to the rescue came the mellow baritone of Dietrich Fischer-Dieskau, who spent his whole career trying to make singing in German lyrical again. He has left a permanent influence. Listening to Simon Keenlyside's recital of Schumann songs later that day, the line of descent seemed clear. Yet there is a big difference: in song you can be intimate; you don't need to yell over trumpets and trombones. Fischer-Dieskau brought a song performer's manner to the stage.
Lloyd, treating opera in a world of its own like most of his colleagues, did a U-turn and reverted to a bout of gasping admiration for the colossal voice of Hans Hotter. I heard Hotter live, and know how fine he was. But this extract had him sounding crude and over-vibrant, fighting a grotesquely inflated orchestra through Wotan's "Farewell". The noise-mongers were the Vienna Philharmonic conducted by Georg Solti, no less, and they set off another train of thought that Lloyd ignored. Surely the real villains are conductors and the builders of big opera houses. They have made louder and louder music fit into ever greater spaces, and the voices can't take the strain without becoming - well, Germanic. So our prejudice in the end is musical. It's what we call it that gives away the xenophobia.