Yes, output impedance for #6F6 and #47 tubes is about the same.
Norm
:I have a speaker that was used in a set having an audio output tube of 6F6 and want to use this speaker in my radio that uses a #47 for an audio output tube. Will the audio output x-former for the 6F6 work with the #47? (The 6F6 audio x-former is mounted on the speaker.)
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