George Crumb “is noted as an explorer of unusual timbres, alternative forms of notation, and extended instrumental and vocal techniques,” according to the opening sentence of his biographical entry on Wikipedia. That certainly fits my experience of sitting in on a rehearsal of his 1969 piece, Madrigals (Book IV).
Instrumentation itself was unusual: soprano voice (Lucy Shelton); flute (Jessica Petrasek), harp (Marion Ravot), double bass (Lizzie Burns), and percussion (Sam Um). And at least for the rehearsal I sat in on, they did not exactly perform: they figured out.
How to get the right sound out of the instrument? How to enter together? How to count at the same rate? How to see one another for cues?
As a listener, not knowing the piece, and not hearing any obvious pattern, it was difficult to find the expressive center — or rather, the expressive center for me, trying to find some resonance through drawing the gattling-gun sounds from the musicians.
I think what I land on is something of an embrace of dissonant, alien, and even not quite cohesive forms looking to mesh despite themselves. I am fairly certain my drawing falls short; from what I understand, once Crumb is nailed and performed (as it no doubt will be), the outcome will be an achievement of the opposite: something pretty special.