Not sure about that, Michael. The Great Exhibition was in Hyde Park. When it closed many of the exhibits (perhaps including musical instruments) were actually acquired by what would become the V&A.

As I understand it, F J Horniman collected some 200 instruments, a few no doubt from exhibitors at the Crystal Palace at Sydenham. However, many of the rest of the museum?s thousands of instruments were from private collections (Adam Carse collection, acquired in 1947, Percy Bull collection, 1948, Arnold Dolmetsch collection, 1983, and the Boosey & Hawkes collection, 2003).

Still, you?re right. There must be a suitable building somewhere in Forest Hill despite our being, as the ES journalist has it, ?somewhat off the beaten track?.