Even so, no big deal, generally harshness would vanish somehow quickly and bass will get tighter. You can have the pleasure of knowing how a particular tube will sound in its lifetime.
For new/NOS tubes, transducers (cartridge, speakers), new amp...etc. I’ve always just listened to music and not sweat the burn in. If a piece is defective or you just don’t like its sound in the context of your system, you’ll know if from the onset and burn in won’t help much, or at all. Music is more enjoyable versus pink noise or test tracks.
OP, gotcha. It does change the sound, and (again) it's interesting to hear the changes.
I'm amazed at how many people are telling you to just plug it in -- as if there are not a million threads about tweaks, techniques, etc. You're asking a reasonable question that many have asked before (in one form or another) and you're getting your head patted as if you were over-worrying. This is a hobby and we're on a hobbyists' forum and you're asking a hobbyists' question.
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