Susan Alcorn Quintet, Pedernal (Relative Pitch) Alcorn takes the pedal steel into new terrain by deftly combining pleasingly melodic quasi-folk and country-tinged pieces, free improvisation, neo-chamber music and post-bop for a genuinely impressive outing. Acoustic bass, violin, drums and especially Mary Halvorson’s impressionistic guitar make for a potent combo, but it’s the slippery, syrup-toned pedal steel playing that’s...