El34 = KT88 = KT120
Tube comparisons are only valid when the same amp is used with all the tubes in succession. Boy, as the resident “expert” you sure make a lot of non-expert comments. EL34s, KT88s and KT120 have different plate and grid voltages, they have different cathode current ratings. Ergo, they CANNOT be compared on the same amp. An amp will be optimized for one and not the others. |
@yogiboy Look at the specifications for the tubes.https://frank.pocnet.net/sheets/129/e/EL34.pdf https://frank.pocnet.net/sheets/086/k/KT88.pdf Plate voltage for EL34 used in push pull operation is 450v, it’s 560v for KT88s in push pull operation. Sure it will work with the KT88s, but not optimally. Same deal for switching between triode and ultra linear / pentode. You want a higher plate voltage for triode mode. Ultra linear / pentode operation will also need more nfb than when operating in triode mode. If it’s optimized for one, it’s definitely not optimized for the other. Doesn’t mean it sounds bad, but it’s not optimized as well as it could be. Besides, what are you doing with push pull amps? Get a SET amp and join us on the dark side. 😂🤣 |
@donvito Quite an impressive marketing spiel you got there Don ... If you understand circuit design and you know what biasing does, you’ll recognize it as marketing hype. The circuit is (most likely) optimized for the smallest common denominator, in this case an EL34 operating in pentode / ultra-linear. The auto biasing will not bump up the plate voltage - and we know for a fact it doesn’t as the output is the same for EL34 and KT88 on the PL. An optimized KT88 has a much higher output that an EL34. (Tip, look at the tube specifications) Since they don’t even mention NFB, they probably don’t reduce that for triode operation either. Not optimized by any measure. If you understand circuit design, you’d know this. If you don’t, then we are wasting each other’s time. " Adaptive AutoBias is completely passive and NOT in the signal path" Telling me a PL is "special" as the auto biasing is not in the signal path is like saying a Toyota is special for having a steering wheel. I don't even know if you can get an amp with a biasing circuit in the signal path. And hyping auto biasing as being "passive"? If auto biasing wasn’t passive, it wouldn’t be "auto" biasing now would it? Folks in marketing tend to exaggerate ... a lot. |
Miniscle nuances,= same To you, I guess so ... I have no reason to believe you are anything but truthful and I am not suggesting you are not. Where you go off track is assuming the rest of us have the same inability to hear the differences when the differences are quite blatant to myself and a few others on this forum. Honestly, I thought you were joking when I first saw your comments. |
