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Haven't tried it but the specs are not encouraging for use in my or any other KT-88 or KT-120. Note the bias is only -14 where a KT-88 is about 40V. The transconductance is about twice the KT-88 which may cause amps to oscillate.
you can set the bias (idle current) for 30 MV (30MA) for EL34 and 50 for the KT-120
Thanks Roger. Can you guide us on what sort of subtle differences we might expect for KT88 vs KT120 vs EL34 tubes? Also, there was some discussion on the forums that suggested you didnt exactly recommend the EL34 for the RM200II- Is that an inaccurate statement? I'm wondering why at least one other person mentioned that to me, and yet your comment would suggest that they are fine to use.
yes get the EL34 Siemens from roger. i tried various tubes in my RM9SE( came with the Siemens) such as Valve Art and JJ e34l's. The Valve Arts were very warm sounding with a muddy bottom end. The JJ's were quite good but they tended to self destruct after only about 150 hrs. So after all of this i went back to the Siemens. Roger is correct they are a fantastic tube. very smooth and continuous from top to bottom. a great midrange, airy top end with a very good bottom end. all in all a dam fine well balanced tube. they are not cheap but well worth it. roger sent me 8 very well matched tubes and they are fine. they take about 50 hrs before they start to sound really good but right out of the box they are good.rob w.
The RM-200 is rather unusual in that the B+ is 700 V and the screen is 320V. The answers to watts, bias and loads and etc is not a simple one but one I do cover in my classes. As I have often stated, bias has nothing to do with output power. I get 100 watts per pair because of the chosen operating parameters mentioned above.