You'll notice change and settling between 100-150hrs. No need to leave them on 24/7, and 20-30min warmup seems to be fine. I run the former TJ Full Music 6SN7 previously noted as being one of the OEM for Sophia 6SN7s but may have changed over the past few years . They are nicer tubes than some of the other re-issues and vintage N7s I've tried, still running them now. Hope they last longer than a year or more.
