Hi Al. I would suggest listening to Al. He and I discussed this very same topic quiet some time ago. My speakers, Roman Audio Centurions are an 8-ohm rated speaker and I am running them on the 4 ohm taps on my tube amp. At first I didn't think there there would be a difference, but Al was right, there is. Try it and see for youself.
SHAMELESS PLUG: Al does make a really awesome tube amp, I use one.
SHAMELESS PLUG: Al does make a really awesome tube amp, I use one.