The new collection on Ace Records’ BGP imprint packs a mighty punch. That’s because it’s dedicated to Horn Rock (with the equally-important subtitle And Funky Guitar Grooves), that boldest and brassiest of rock subgenres. The phrase “horn rock” immediately brings to mind the sound popularized by Chicago and Blood, Sweat & Tears (only one of which is represented here) but the added colors afforded by horns were applied to recordings in the baroque-rock, art-rock, psych-rock, and jazz-rock idioms, just to name a few. This 17-track sampler from artists both unfamiliar and unknown…