So, I have an egnater tweaker 15, I recently had an issue with a blown resistor and shorting tubes. I replaced the resistor and put in new tubes. The only 6v6 tubes I could get on short notice were groove tubes from guitar center. The tubes that were there before were tung sols. Since putting in the new tubes and resistor the amp has been quieter than before(noise wise), but, it sounds very sterile and lifeless compared to prior. Could it be that I just need to break in the tubes? Are groove tubes that bad? I was considering getting a set of 6L6s and maybe some new preamp tubes too, would that be of any benefit?