Not one to dish out 10 out of 10 easily (check my other verdicts!), I must defer one to this film.
It has been years since I saw it, but it is one of half a dozen films I'm still hassling the DVD shop if it will be available on one.
All the elements of a great film are there, ruined if it had been shot in colour, ruined if the tune had been played on a piano, ruined if the echoes had been on modern Hi-fi, ruined if it had been any other way.