ORR is a continuation of the English Baroque Soloists, which was setup
when JEG entered the 19th-century repertoire (hence the strict division
of repertoire between those two).  As far as I can remember the set of
Beethoven's Symphonies was their first major undertaking and the name came
from JEG's believe's that it was fascination with revolutionary ideas that
set apart the Romantic art (and Beethoven's music in particular) from
other periods in music history.  If there are any differences in personnel
between those two orchestras they are only due to the fact that at the
time when ORR was setup quite a lot of British HIP players left the
conductor-driven HIP ensembles such as English Baroque Soloists, London
Classical Players and the Academy of Ancient Music to form the independent
Orchestra of the Age of Enlightenment.

Pavel Kotla