Isn't anything over 20 years considered classic? I know classic isn't the same as vintage though. To me...vintage means something that is old...was made during a certain time period that is supposed to have some significance. Either in popularity or quality of the product. Look at wine. Wines come in different "vintages". Depends on the grapes I guess?
I think Nelski is right though...vintage brings on a certain vibe. Perhaps certain guitars and amps take you to that place thats universal for almost everyone that's tapped into that vibe? Sort of a collective agreement that this such and such guitar is a precious commodity that one must play at least ONCE in their lifetime. OR OWN. Very interesting topic.
Guitars/Bass - MIM Fender Classic 50s Strat, MIM Fender Standard Strat, Squier Classic Vibe 50s Tele, Gibson Les Paul Studio, Epi '56 Gold Top Les Paul, Martin DSR acoustic, Sigma Martin Auditorium electric/acoustic, Squier Jazz Bass.
Amps/Cabinets/Modelers - Model 2558 50 watt Marshall Silver Anniversary Jubilee combo w/ Celestion Vintage 30s, 4x12 Marshall cabinet w/25 watt Greenback Celestions, Fender Blues Junior w/ a couple of Billm mods, Line 6 POD 2.0, Roland Micro Cube
Pedals/Effects - Cry Baby Classic Wah, Boss TU-2, Boss NS-2, Boss RC-2 Loop Station, Ross Compressor, MXR Micro Amp, Danelectro FAB Echo, Danelectro FAB Chorus, Danelectro Chicken Salad, Marshall Guv'nor Plus, Marshall Echohead, Duhvoodooman's Zonkin' Yellow Screamer, Digitech Digiverb, Digitech Bad Monkey, Dunlop Fuzz Face, Homemade Loop Bypass pedal, Duhvoodooman's Sonic Tonic (Maxon SD-9 clone +), Voodoo Labs Superfuzz