Could I just remind folks......

[Arkless Electronics]

Other than the obvious of how old it is, define age in hi fi gear? Quad 405 for example came out in 1976 but it could be argued that the current dumping technology is still the most recent innovation in hi fi... class D is old hat BTW and predates current dumping by decades, even though it's only fairly recently that component improvements and cheaper manufacturing have made it fairly common.
Circuit design and parts used in some of the most advanced Jap amps from the late '80's is still pretty state of the art, and more so than in many modern amps!

Do we define an amp as vintage because it's over 25 Years old? Because it's styling is obviously from another era? Because the circuit design and parts are from another era? Because it sounds in some way "vintage" (and define that!)?

[Audio Advent]

Because it's styling is obviously from another era?

Yep!

If it looks old fashioned...

[Barry]

How do you define 'vintage'? Well that's simple: it's the sort of old tat that Barry still uses. '

[Marco]

Some of that 'old tat', however, can be rather good. I've got a fair wedge of it myself!

Marco.