export function simpleTuning (src) { var pcs = map(pc, tuning(src) || src) var simple = pcs.reduce(function (s, pc, i) { if (s === false) return s else if (i % 2 === 0) s.push(pc) else if (s[s.length - 1] !== pc) return false return s }, []) return simple || pcs }
export function scale (tuning, scale, first, last) { var filter = map(scaleFilter(scale)) return build(tuning, first, last).map(filter) }