So you’ve adjusted to the new music economy. You know the big acts have little to gain from making the album of their lives, because only a few of their fans will actually buy it, and most of them will listen to it on terrible-sounding earphones anyway. The money and the passion previously reserved for albums are being redirected into touring. U2 is travelling with a stage set that takes two days to dismantle and pack up. God bless the big guys for bringing the big toys—sports arenas and concrete tubs are not often a friend to the sonic arts. So when Metallica comes to town, go. They’ve been perfecting the art of loud for years. Like Nine Inch Nails and other scientists interested in splitting the ear, Metallica knows the secret is in the low midrange and not in overdriving gear that can’t be overdriven. I haven’t cared for a Metallica album in years, but the band can still make a stadium rumble. At Madison Square Garden on Nov. 14-15, their music won’t sound like it’s ricocheting around in a toilet. It will sound like metal, not concrete.