Do I turn off my tubed components during burn-in?

I new to the world tubes and tube equipment. I just received me Dared SL-2000A pre-amp and my 300b SET monoblocks yesterday. Unfortunately I can't use the amps because because I'm saving to buy a pair of TJ Meshplates ($325). In the meanwhile, I did hook up the pre-amp last night to my Parasound HCA-1500A. Sounded pretty good last night,,,,,,,,,,,,,,,,,,,,and believe it or not,,,,,,it sounds even better last night. My question is regarding burning in the tubes. Should I leave the pre-amp on all the time for a few days or is this a bad idea with tubed equipment?