To simply answer your question -- tubes have nothing to do with volume that I know of.
If you're talking about a lower/higher noise floor -- that is certainly possible.
The thing that baffles me in that you say, "I've got the preamp at about all the way turned up." Just about every active preamp I know of has enough gain to drive any amp into clipping. Why don't you back off the volume a bit on the preamp so the tubed amp doesn't clip when it runs out of steam on on peaks. That is definately not good.
50wpc is not a lot, but without knowing what preamp/amp/speakers you are using, its kind of hard to give good advice.
Of course if your preamp is of the passive level control variety, ignore this.
If you're talking about a lower/higher noise floor -- that is certainly possible.
The thing that baffles me in that you say, "I've got the preamp at about all the way turned up." Just about every active preamp I know of has enough gain to drive any amp into clipping. Why don't you back off the volume a bit on the preamp so the tubed amp doesn't clip when it runs out of steam on on peaks. That is definately not good.
50wpc is not a lot, but without knowing what preamp/amp/speakers you are using, its kind of hard to give good advice.
Of course if your preamp is of the passive level control variety, ignore this.