is it ok to leave a tube amp on without speakers connected


I'm blessed to have two amps but one set of speakers in my listing room - all tubes.  Instead of cutting off one to listen to the other, I would like to listen to the other without powering off the one i'm not listening to.  

Question:  Can tube amps be powered on without speakers connected for hours at a time?
mudbone
No, I don't know the specific reason, but was told that the speakers provide a load on the amps, and especially for tube amps, it's not okay.
Octave Audio tube amps can be run without a load but, you really shouldn't be connecting/unconnecting speakers under power any way.
No, and agree you should never connect and disconnect speakers with the amps on in any case.