by Ty_Bower » Thu Aug 20, 2009 11:38 am
A little reading suggests the Mullard 5-20 circuit used a EF86 pentode in the front seat to get boatloads of gain. Something like 50 mV for full output, even with feedback applied. It was suitable for use with your "gramophone" without the need for an expensive pre-amplifier circuit. Alternatively, you could opt for the passive tone control network and still drive the thing with a 600 mV input.
I'm not sure I need that much gain in my driver circuit, and I don't have a spot for bass and treble knobs. What's wrong with using a triode instead of the EF86?
"It's a different experience; the noise occlusion, crisp, clear sound, and defined powerful bass. Strong bass does not corrupt the higher frequencies, giving a very different overall feel of the sound, one that is, in my opinion, quite unique."