6L6GE help / info needed

[AJ_Newkirk]

I was just reading an old post where Boogiebabies stated some info regarding the current draw on #5 6L6GE's from Groove Tubes - and how they do not properly bias in a C+ if using the #5's. Hopefully Boogiebabies or another guru can chime in on my question below.

I am about to buy some tubes this week and the 6L6GE was near the top of the list of power amp tube ideas for my Mark IV. Which GT rating would you recommend I use for installing the 6L6GE into a new Mark IV? I would be running 4x6L6GE's if the tube type makes any difference between the inner/outer sockets.

Any other currently available power amp tubes that you would recommend over the 6L6GE?

Any info/advice would be greatly appreciated!

 

[fishyfishfish]

Call GT and ask what they think. They were cool with my questions.

 

[Boogiebabies]

Not too many tubes do bias to 75% MPD in the Boogie's. Without a bias pot, it's what we all have to deal with. The GT # 6 6L6GE biases on the cool side at 22ma at -56V with 483 plate volts which is exactly where a $ 150 duet of STR-415's bias. Neither tube sounds grainy or brittle and they have huge lungs. In buying virtually every brand of tube for these amps I have learned that it is extremely hard to buy a tube from a vendor that will get you to 65-70% MPD. It's like trying to shoot a flea with a needle from 10 yards. The vendors just do not know the variables to sell you the tubes, and if they did, they would probably send you cooler running tubes because warranties on tubes are a nightmare to get funded, unless you have a top notch supplier. Another issue in trying to get a higher plate current is that vendors seem to only test for natural plate current at 450V ( Maxi Matcher) and a bias draw that is different from your amp. If your amp has higher or lower plate voltage than the test equipment, no one knows where your bias reading will be in relation to the numbers on the tubes. After amassing a closet of tubes, I have just conceded to using a few brands from two vendors. I get the GT's from Doug's Tubes and I use
NOS Svetlana ( Winged C now ) # 35 6L6 and # 32 EL34's from Triode Electronics. The tubes from Triode bias at 35ma across all four in Simul-Class and were all exact to the milliamp in matching, and they remain so after two years of use.

Happy tube hunting !!!!