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RE: 5755 and a ll1630 for preamp

Posted by amnesiac on February 22, 2025 at 19:28:40:
Forget about it. With an Rp as high as these of the 12Axx you will get MASSIVE frequency response problems with an output transformer. You will need an ungodly inductance for an acceptable LF rolloff and that many windings will give you a hell lot of interwinding capacitance screwing your HF response. so au7 is out 6j5 types left
edit should I start drilling?: ^)ah 12b4 across parallel winding 12 has low rp low enough? Ilike 12b4 my epay name. Holding back on the step drill until somebody help me do the math i'm a fitter turner done 1st year radio and tv 20 years ago. I just bias and listen. Need to get a scope. learn more.
Ok found 6 6cm7. According to data I can run 200v 5ma on plate hows that?