Electro Harmonix 6L6eh, Dual Rectifier question

I searched for the answer before I ask this, but didn't find anything. I just bought a used 2 channel Dual Rectifier that has Electro Harmonix pre/power/rectifier tubes. The power tubes are 6L6eh's. As soon as I fired it up, there was a pretty loud hum. I swapped the power tubes out with some Mesa tubes that I had and found the problem tube. I called Boogie to ask them a question and he said that the tubes should be in the middle of the testing range. He explained that Groove Tubes test 0-50, some others test in different ranges, so as long as it is in the middle and not at either end, it should be fine. After checking the tubes and calling TubeDepot, I found out that they're a 15, with a test range of 12-33 (obviously not in the middle). I called Boogie back and the guy I talked to this time really didn't know anything about being in the middle of the test range, and said that the only way to check to see if they're Ok to use is to have someone check the bias while it's on. I probably won't do that, but I'm wondering... if I leave these low number tested tubes in (but replace the bad one with the same brand/number) will it be Ok and not hurt anything? The guy at TubeDepot said that the number is just an indication of how soon the tube will break up in relation to a different test number.
Thanks for any replies,
Paul

Bump

Ditch the tubes that are in it, and buy either some new Mesa tubes, Groove Tubes in the range 4-6 or tubes from a reputable supplier that will supply tubes within Mesa specs. Why do people spend loads of money on equipment and try to save a few pennies on tubes ?? Crazy. :?

After reading your reply where you mentioned that if I bought Groove Tubes they should be in the 4-6 test range, I did a little more research and you're right. That would be right in the middle since Groove Tubes tests in a range of 1-10. The guy at Mesa said that Groove Tubes tests in a range of 1-50 which after reading your reply, sounded like 4-6 would be too low. I think he must have been thinking of another brand. Thanks for your reply and for clearing that up for me!

I agree with ANIMATED SUSPENSION ditch the tubes and put all brand new power tubes in, either Mesa or Groove Tubes. I just completely retubed my Dual Rec and it screams. It's not worth the hassle of damaging other components by trying to save a few bucks.