Badlander tube bias testing

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GJgo

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Hey guys. So every Mesa amp I get I test & record the tubes that I have on hand since there's nothing I can do about the bias, and I prefer to be in the 60-65% dissipation range tonally. We all know Mesas are biased cold for tube longevity & it usually takes some work to bring them up. With the old amps no big deal, but with the new ones we have to use Mesa tubes to maintain our warranty. So...

I picked up a Badlander 100. Loving it in the band so far!! Might not be my favorite bedroom amp though compared to the vintage rigs. I will say it has Mark-like bounce, bloom and high gain note separation, is tight, and does not do the "wall of sound" thing. So far I'm not really seeing any Recto lineage here. I'll also add that for this amp I really do think the EL34s sound better. IMO. Interesting to note that in the manual, they reference the amp's "British heritage" a few times. Anyway..

The amp came with a quad of Mesa 447 (EL34) in Grey. As we know, the Mesa color code system runs from cold to hot like this where each color range is a few mA hotter. That said, I'm used to seeing a significant spread in mA in the amp from any given color code set and if I'm being picky I'd need a few sets to get pairs that are within 5-7% or so.

Red
Yellow
Green
Grey
Blue
White

So here's the data. Plate voltage today- Variac 391, Bold 447. We'll use Bold for testing. Ok, we're not at risk of smoking tubes from voltage.

Testing tubes in Bold mode-

Mesa EL34 447 grey- 16-19 mA which is around 32%. Cold!! I'd like to go straight to white & re-test.

Mesa 6L6 440 grey- 22-24 mA which is 34%. Cold!! Note for testing I briefly switched this up to EL34 bias which is hotter to see where it lands and it was in the 60+mA range which is >100%, so, I immediately shut it off. Though, this "may" be usable with Red. Maybe. Also note Grey is optimal for every 2 or 3 channel Dual or Triple Recto I've owned.
 
Hi, great info.

Question: early in the post you mention you like to run 60-65%. But later you say that 60% is greater than 100% and you quickly shut it off. Can you please explain that difference? Thanks
 

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