The Scottish Chamber Orchestra, founded in 1974, has enjoyed a world reputation for some time now for the work they have achieved over the years under Sir Charles Mackerras, who still conducts the orchestra on occasion. And they are anything if not versatile, playing a repertory spanning the Baroque and the contemporary. Saturday evening they were in their Classical mode, playing Haydn and Beethoven with a slightly relaxed compliment of original instruments (i.e. cellos on pins and metal flute alongside gut strings, natural horn and trumpet, etc.) under the direction of the brilliant Swiss conductor, Thierry Fischer. The evening was a splendid success, full of imaginative insights and intense music-making. The orchestra and singers seemed to enjoy it as much as the audience, a special distinction for Mr. Fischer, who conducts without a baton, using vigorous, occasionally extravagant gestures, which never failed to bring the musicians together in committed playing and tight ensemble.