Burn-in is at very least 100 hours with music or XLO break-in tracks. Bryston's break in is with a single test tone at 10KHz, great for weeding out weak components, not so good for music. My 6B SST's are comming along nicely at about 150 hours of music and XLO break-in tracks for maybe 30 of thoes hours. I upgraded from a 4B ST and the difference in amazing. ENJOY
