In a blacked-out, echoing old warehouse somewhere north of London’s Liverpool Street, we are mooching around flashing torches at each other and being told to shut up by security goons. The murmuring is silenced by a Latin motet coming from all around in the darkness: “Hei mihi, Domine, quia peccavi…” The chords are odd, shifting, curdled: this is the sixteenth-century polyphonic sound world of Palestrina, but something has gone wrong, as if an old vinyl LP had been left out to warp in the sun. Welcome to the world of Carlo Gesualdo, where tortured words of love, death, sin and bitter repentance are expressed through music unlike any other, where harmony itself is stretched and twisted and tormented to express the agony of uncontrollable emotions.Gesualdo is known