Thanks to the Orchestra of the Age of Enlightenment, and others, historically informed performances of Classical music are now a regular thing.
However, as any expert will tell you, musical authenticity involves more than just period instruments: it's also about weight, balance, articulation, phrasing, rhythm and expression.
In his account of Beethoven's Symphony No. 8 conductor Mark Elder paid deference to these requirements, but for all its nicely proportioned playing, period sound and orchestral layout (violins on either side, woodwind sandwiched centrally between lower strings, trumpets and horns the outer wings) it was an unconvincing, charmless reading. The heavily accented opening Allegro seemed unusually ferocious (though sparkle was eventually achieved in the Finale) and the two middle movements had too much gravitas.
Rossini's Stabat Mater was a real oddball, combining authentic orchestral sounds (the OAE fully alert to subtleties of colour and attack) with general-purpose solo-ists and chorus.
That apart it was an effective and, in choral terms, most exciting performance. The opening was wonderfully dolorous, the huge London Symphony Chorus (I gave up counting them, but the programme listed 197 singers) producing a superbly balanced, 'finished' tone, gloriously effulgent at full throttle yet delicately burnished in the quieter passages.
Much later the Quando corpus morietur displayed impeccably nuanced control and tonal beauty, and the final Amen chorus came over stupendously well - a textbook example of thrilling choral counterpoint and brilliant execution.