One hour for warm-up is fine for the tubes themselves, but I've had some components that most certainly do sound better when left on all the time. The Pass Labs Aleph 5 amplifier I owned got better sounding after one or two days of warm-up, but I'm relying on my aural memory to make that judgement. Seems like the Class A stuff does better when it is left on longer, and I'm guessing it has more to do with the SS components, and the non-glass parts of tube gear. Someone tell me if I'm nuts here, or is there something to that. Yep those small signal tubes last about a year if left on all the time, but that will also depend on what pre-amp, which tubes, and how hard you drive your system when you do play it. My buddy tells me his Audible Illusions consumes 6922's pretty quick and the good ones are rather pricey, especially for a matched quad. Also, if you have a class A preamp with a larger transformer your electric bill will certainly reflect your decision to leave the pre on 24/7. I'm not familiar with the Dared. Definitely get rid of those Chinese tubes and get something better. Along with the list above, add to that GEC 12AT7's which are among the very finest out there but harder to find (this is definitely a shameless plug for the fact that I have a minty pair for sale right currently on A'gon). Seriously those are a great choice in that tube type as well. The others were also good reccomendations.
Marco
Marco