Bias question for Vibro-King

[docmh]

I have a Fender Vibro-King. I've never measured the bias by -46vdc as stated in the service manual below but have used the ear method as described. I also have a bias meter to check mv's. With a set of tubes in the bias meter, I'll turn the bias knob all the way up and a set of Wing C's will show 50 mv's on my meter. Can I assume that if I lower the bias to 35mv's I'll be ok? It always seems to come out that way after I check it by ear too.
I tried a pair of Jan Phillips WGB's in my amp today. I know they're not 6L6's but am told they can handle high plate voltages OK. When I put the tubes in my bias meter with the bias control all the way up, the meter shows 65 mv's to 12 mv's at the lowest point. I lowered the bias to 40mv's as that seems like roughly 60% of the high bias range to me. I still don't know if this is all right. The plate voltage on this amp is around 470 volts. The amp sounds good, but I don't want to fry the tubes either. They don't appear to be running hot.
Does any of this make sense to anyone?

From Fender VK service manual: BIAS PROCEDURE: The bias, measured at pin 5 of V7 or V8 should be set to –46Vdc. However, the Bias need not be measured to be accurately set. To set the Bias without removing the chassis, set the Volume knob between 1-1/2 to 2. (The Bias control is located on the under side of the chassis, next to the power cable.) Adjust the Bias so the amp produces the maximum Hiss. Strum a full chord and let ring. Now, turn the Bias control back just to the point that the sound of the guitar loses warmth and sustain.
Then increase it slightly. This will ensure minimum crossover distortion and the best sound.

[philo43]

40 ma @ 470 volts will be about 18.8 watts at idle (disregarding the screen current). You are well within the operating specs of the tube. You could even run it a bit hotter, I would think. Looks like as long as you avoid extreme settings, and go by ear you won't damage anything. BTW, I like the "ear" method of setting the bias in a push/pull amp. When it comes to crossover distortion, hearing is believing.