So the voltage can be higher, but it's best not for the voltage to be lower. 16v or higher it is, then.

In the light of what has been said, a little further clarification of the µF value would also be useful, so if I can impose again: will use of a higher rating (say, 100µF, 16v) also cause problems where the original was 47µF, 16v? Is the 47µF a minimum rating, like the voltage, or something else?

Alas, these are things I ought to know – but I do not.

Many thanks. All this is very helpful.