Re: 8ohm vs 16 ohm speakers / cabs
A Marshall Plexi may sound slightly different with the selector set to a different setting, but that is at the Output Transformer. Mis-matching the sector to the load will also cause a slight diffrence in tone, and it's one of Eric Johnsons tricks, but this isn't the speakers themselves sounding different. To be more specif, it's between the the output transformer secondary and the OPT primary/tubes, not really the speakers. There's no diffrence between a 8 ohm speaker and it's 16 ohm version in my experiance.