IMO, you should go to the Cary website, get their phone number and call Kirk on Monday with your question.
Tube Replacement: Single, Pair, or Quad?
Hello, can anyone help me?
I have a new (to me) pair of Cary SLM-100s. Without fail one of my amps will blow a "tube" fuse after approximately 45 minutes of listening. Immediately prior to the fuse blowing, two of the tubes (positions 3&4) become very bright. After this happened a few times, I switched Tube #4 in one amp with Tube #4 in the other amp with similar results in that amp.
I am using Tesla KT88 power tubes (not JJ Tesla.) I have them biased to approximately 150ma.
My initial diagnosis was that I have a bad tube. However, my question is, if the tube is OK, why would it continue to operate correctly in 45 minute increments? Could something else be wrong? If I need to replace the tube, do I have to replace tubes in pairs (e.g., 3&4) since this is a push-pull design? Do I have to replace all four? Can I just replace the one bad tube?
Also, the original owner did not have this problem. Further, when I installed the tubes I did so randomly not knowing which tubes he had in which amp in what order he had them in. Is this relevant?
Thanx in advance for your assistance.
I have a new (to me) pair of Cary SLM-100s. Without fail one of my amps will blow a "tube" fuse after approximately 45 minutes of listening. Immediately prior to the fuse blowing, two of the tubes (positions 3&4) become very bright. After this happened a few times, I switched Tube #4 in one amp with Tube #4 in the other amp with similar results in that amp.
I am using Tesla KT88 power tubes (not JJ Tesla.) I have them biased to approximately 150ma.
My initial diagnosis was that I have a bad tube. However, my question is, if the tube is OK, why would it continue to operate correctly in 45 minute increments? Could something else be wrong? If I need to replace the tube, do I have to replace tubes in pairs (e.g., 3&4) since this is a push-pull design? Do I have to replace all four? Can I just replace the one bad tube?
Also, the original owner did not have this problem. Further, when I installed the tubes I did so randomly not knowing which tubes he had in which amp in what order he had them in. Is this relevant?
Thanx in advance for your assistance.