Back in ye olde days, I had a pretty sweet system. Bose speakers, Denon receiver and cd player, and the oh-so-pricey gold Monster Cables connecting everything together. I was a sophomore in high school, and I saved up (Jewish) confirmation gift money, went to Tweeter’s “Scratch ‘n’ Dent” sale, and lugged it all home on the T — from Harvard Square to Oak Grove...