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Tung-Sol kt170 tube started glowing brighter

I installed 8 Tong-Sol kt170 tubes in my Sonic Frontier Power 2 amp. One tube started glowing a bright orange, yellow at the lower portion. I hear no sound interference. Should I replace it? If so, replace paired, right channel quad or all eight for matching purposes? I did swap the tube into different socket and it is the tube.

128x128kitegod
ibmjunkman's avatar
ibmjunkman
244 posts
 

Thermal runaway. Runaway yourself!

dekay's avatar
dekay
5,556 posts
 

Don't reuse the tube that glowed red (not worth the risk).

Pretty certain the P2 has individual bias adjustment for each power tube and if this is the case pick up a new replacement and bias it per SF's instructions.

 

DeKay

kitegod's avatar
kitegod OP
36 posts
 

That's what I wanted to be assured of.   Thanks

speedthrills
160 posts
 

@kitegod , Yes, you can replace the one bad tube with one with similar numbers on it and then check / reset bias. If your amp isn't rated for the KT170 despite being told it should work it might be safest to revert to the tube types that are specifically compatible with the amp? I guess the other option is get the new KT170, install it, check bias and see what happens- it may have been an isolated incident with the one bad tube. 

yoyoyaya's avatar
yoyoyaya
742 posts
 

@OP The tube is starting to red plate. Don't try to rebias the tube as it will only hasten it's demise.

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