Some Schoeps capsules have for many, many years had frequency
response well beyond 20k. In typical fashion, Schoeps simply did not
advertise this feature. In the old days, or the golden days, you were
given a choice of whether you wanted a matching preamp body *with*
extended frequency response or without. This practice was discontinued
as it was confusing. People asked, why would anyone want to record up
there? Others said that they did not want to record those frequencies
for the same reasons that are valid today, eg artifacts, junk.
Although the frequency response of the capsules has been modified in
some cases over the years, the ones that are not "rolled off"
generally go up pretty high.
DT (from MpH)