Problem with biasing


Hi, I have a citation 2 and recently re-tubed with gold lion kt88. I noticed that tube 8 was glowing a little more than the others. So I checked and it was 1.7 volts. My other tubes are 1 volt. Bias 1.68 volts is the lowest I can get which is still too high. Anyone ever have this happen?

kellymack

It was the tube. I was able to bias them all to .97 volts… that right, what would that be in ma? I have 2 amps for a bi amp system. Yea one is in ma and the other volts? I like if they’re 85 ma

😊👍

 

Tube problems are not common, but if you get a whistle, bright tube, or weird poping, that is the place to start. Because most tube equipment uses more than one of the same tube, diagnose can take a couple minutes. 
 

My systems run over forty tubes and I get a strange sound every couple years or so… typically associated with a new or relatively new component. 

Hi Kelly.

My systems are shown under my user ID.

I have Audio Research Reference Phono stage, preamp, DAC/ CD player, and amps, Woo head amps WA6, WA6SE, WA 5, and a PrimaLuna integrated amp. I’m thinking about $100 in the last ten years. I had to replace the Prima Luna tubes, and I traded in my Audio Research Reference 5SE for a Reference 6SE before it needed new tubes.

So, I think this is why folks talking about the theory and reality of tubes are so far apart. I had a Sonic Frontiers tubed CD player for fifteen years… the cd transport needed changing out three times, the tubes, none.