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RE: A critical inductance choke input filter....

Posted by Ian L on May 15, 2023 at 14:55:29:
Hello Tre'
I remember that in the early 2000's a lot of the discussions of tube cathode heating were about the differences between regulated and non, as well as differences between voltage regulated and current regulated.
If a regulator is used the supply that feeds it might have a lot less impact on the sound.
Rod Coleman's design idea (as I understand it) of putting high impedances at both ends of the cathode in a DHT does seem to have merit as his regulator's do make for good results. I guess that might line up with your use of the choke on the output of your supply. I don't remember who it was back then but there was another Asylum member who talked about his supplies having a choke in series with each end of the filament to good effect.
Bottlehead had a design that used the leakage inductance of a (Paul Joppa designed?) dual bay choke (search "Bottlehead FC-1") to act as a common mode choke.
P.J. also posted a circuit in the post linked below that shows a dual choke design like the one mentioned above.