Ip = Plate current. You obviously have the wrong tubes. VTL can tell you exactly what tubes you need. You would be money ahead buying your tubes from VTL. Changing the driver tubes to Mullard "CV" tubes will give you the warmer sound you are looking for.
power tube rating
I have a pair of VTL MB-450 amps, each with 8 6550 tubes. They were retubed in June of this year and now they need total replacing again. I was told that the tubes burned out this fast because they had a low IP value so I'm looking for someone to tell me what this value means, and what it actually measures. The tubes had a value of high 40's - low 50's and it's supposed to be high 60s. I need to know what this value is just so the next tubes I buy will actually last me longer.
Another question regarding tubes. The stock tubes are Svetlana, but does anyone recommend trying something else, maybe the Tung-Sol, SED or EH? Maybe KT-88s? I found the stock tubes to be "hard" sounding, so I'd like something warmer but with a full bottom-end.
Another question regarding tubes. The stock tubes are Svetlana, but does anyone recommend trying something else, maybe the Tung-Sol, SED or EH? Maybe KT-88s? I found the stock tubes to be "hard" sounding, so I'd like something warmer but with a full bottom-end.
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