TimeSignature

[Roland Goretzki]

Hello,

the combination

   \property Staff.TimeSignature \set #'style = #'default
   \time 2/2

creates a symbol like the big letter C with a line cross from top to
bottom, in german called "Alla breve".

Now, my problem is:
How can I put two of this symbols directly one after another?
(e.g.: C|C|)

This is necessary for the following piece of music:

   Impromptu opus 90, no. 3 in g flat major from Franz Schubert

The combination

   \property Staff.TimeSignature \set #'style = #'default
   \time 2/1

creates the correct bar length, but only a symbol like:
        2
        1

and the same at 4/2 with the result of
        4
        2

I would be very happy, if I could realize the original version with the
double-symbol.

Thanks                  Roland