[rbyar]

Good Evening,

Last week I ordered a quad of Gold Lion Genalax KT88. They came this afternoon.  I put them into my Grant Fidelity A-348 and biased them to .48.  Within 5 minutes I had one tube get bright red. It was red for about 3 seconds.  A small burn mark, the size of a dime resulted.  I quickly shut off the unit. I then let it cool for a few minutes. I then turned the bias low and turned the unit back on.  I started with .4 and in 20 min increments moved the bias up to .48.  It has been on for four hours now and it seems fine. Sounds fine. Nothing lookes burned, cracked or broken inside. I know there is a break-in period. But I mean that channel, the right, does not sound different than the left.  Do you think there is any damage to the tube?   

I await your reply and thoughts.

REB.

[jtsnead]

have the same tubes in my Rogue 90, that same think happened to me but it took a few days until the tube went bad, then I could tell the channel it was in was distorted. The tubes were under warranty so Rogue replaced it.
You should get some kinda of warranty if you bought the tubes new

Good Luck,
JT

[rbyar]

I now have approx 60 hrs on these tubes and all seems fine. Even the one that got red. The only thing i have noticed is that i can keep all the other KT 88 tubes at .48 but the one that got red likes to drift to .49. In three days it will drift from .48 to .49. No higher. It just seems to stop there.  Is that an issue or a sign of anything?

Thanks

REB.

[jtsnead]

the .48 you are refering to is in milliamps correct? if so a .1 difference is no big deal. Rogue recommends a bias of 40 milliamps for the Stereo 90