ZZ Top’s 1975-vintage fourth album is an interesting hybrid of live and studio recordings. The first side, all live, is appealingly ‘real’ and exciting, but it’s the second side’s six-strong selection of studio works that really stuns as a demo. Of course, “Tush” is the most well-known cut, the band’s first really big hit, but our favorite song for the speaker sound test is the simply exquisite “Blue Jean Blues”. Billy Gibbons’ wonderfully dexterous blues guitar solo is a treat of technique and tenderness. It’ll image beautifully on your system, sounding stable and focused in front of you as you drive.