I heard a symphony orchestra clearly, in all its glory, for the first time in my life, at the first ever afternoon concert performed in the brand new Royal Festival Hall, on Wednesday, 9th May, 1951.  This was only the sixth concert in the Hall's distinguished history of more than 50 years, so far.  Remember, we were back in the days before hi-fi or even a partial cure for the famous Albert Hall echo.  So Harry Blech's London Mozart Players were a revelation in their precision and clarity, playing a generous concert of a Mozart Overture, both a Haydn and a Mozart Symphony and - the hightlight - Mozart's Concerto No. 24 in C minor, K491, with that superb English pianist, Denis Matthews, at the keyboard.  The Festival of Britain South Bank site had been an eye-opening feast of modern architecture for me and although the RFH looked solid and tradtional in such company - it was the only permanent building, after all - as you approached, your appreciation of it underlying modernity grew.  There was the concert hall, floating on its invisible springs inside the outer shell, mainly of glass. There were the vistas from inside the cool, spacious, calmly modern interior, with its split levels and varied wall and floor treatments. Then you entered the hall itself. Wow! What a climax........