I have a rebel 20 so fixed bias; of course it's a good idea to re-bias it after changing tubes, but I'm wondering if I were to put in equivalent JJ replacement tubes, as close to stock as possible, is doing a bias strictly necessary? I'm not experimenting or putting in a different brand etc. I don't have the tools to bias it myself and am trying to avoid the expense of a tech when all it needs is a new power tube.
