Although rock 'n roll is America's all-time leading cultural export, half of the classic rock sound - hard-hitting, skintight, audacious, and vibrant - was born across the pond. Musician, journalist, and writer Dave Hunter's The British Amp Invasion: How Marshall, Hiwatt, Vox, and More Changed the Sound of Music charts the forty-plus year confluence of British industrial ingenuity and popular culture that grew a minor "also-ran" offshore industry...