@gugliel said:
[edit] -- just read your second post, where you say fff, and a group of celli: for that, divisi is far better [/edit]
Thanks for that Gugliel. I have now been reliably informed by 3 cellists that it is possible.
Unfortunately I cannot divide the strings because it would ruin the balance. It is only a brief instance within the piece, and again when the tune repeats. The violas are playing the melody an octave below both violin sections, unison, Sul G. The melody dips briefly below the lowest viola string and the cellos will cover that and the bass together. It's all doubled with brass so the difference in tone won't stand out too much. But I cannot risk a drop in power at that point, as it needs to be full force. It is right at the start of the melody which requires as much energy as possible.