-- indexInBetween ; index into buffer for frequency values
let f0 = mouseX kr 200 900 Linear 0.1
    b = asLocalBufId 'α' [200,210,400,430,600,800]
    i = indexInBetween b f0
    l0 = index b i
    l1 = index b (i + 1)
    f1 = linLin (frac i) 0 1 l0 l1
in sinOsc ar (mce [f0,f1]) 0 * 0.1

-- indexInBetween
let from = asLocalBufId 'α' [1, 2, 4, 8, 16]
    to = asLocalBufId 'β' [0, 1, 0, -1, 0]
    x = mouseX kr 1 16 Linear 0.1
    i = indexL to (indexInBetween from x)
in sinOsc ar (linLin i (-1) 1 440 880) 0 * 0.1