I'm comparing two original vintage Fender Vibrolux Reverb Combos: 1966 Blackface Vs 1973 Silverface. I'm playing them using a 1973 Gibson Les Paul Custom. I play the amps using their own cabs but I also play both amps through the same 1972 Marshall 1960B Cab with Celestion Greenbacks G12M25 75Hz Greenbacks with Pulsonic cones.