Does anyone know how you can see the age of a bang and olufsen 9500.

 Is there an clues in the serial number?

With newer main products the first two digits of the serial number is the indicator of the year of manufacture. I'm not sure if this sequence holds water for older products but I have always assumed that it does.

If 09 is 1994 you can count backwards through the years and subtract 1 from the first two digits. ie. 08 is 1993.