Even the resistor loaded #26 has enough gain to drive grid voltage of trioded EL84 PSE.
Sample (a little bit decreased B++):
If you want more power (6-7W), must to use EL84 as tetrode (see Schade feedback RH84 variants).
Sample (a little bit decreased B++):
If you want more power (6-7W), must to use EL84 as tetrode (see Schade feedback RH84 variants).
Yes, power is an issue for larger rooms. I don't have that issue myself which makes things simpler - I'm OK with 18W dissipation for the output stage. For my own system I actually use some of the odd base vintage tubes in triode, but these old tubes are far too rare to recommend these days, hence pointing people towards EL12n, 7591, EL84 etc which are not expensive and easy to find. As you say - high gain tubes are easy to drive so DHTs are easy to use with them.
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If the sound character is largely determined by the driver tube, then it would be logical to do the opposite of what Andy suggests: Most voltage gain in the driver stage, and little gain in the output stage. Here is a possible implementation of this principle: 1J29B triode-connected driver transformer-coupled to the 6080 output. I like 1J29B for its low Rp (about 4 K), but many other DHTs can be used with circuit adjustments. The topology is the same as in my previous post. Input and interstage transformers have negligible distortion (except at the frequency extremes), so they shouldn't contribute to the sound character. Output transformer is quad C-core amorphous designed for 6S33S tube, they currently sell them on eBay. Output power is about 4 W. Step-up interstage transformer may seem problematic for driving output Miller capacitance, but 6080 has only 1/3 Miller capacitance of 2A3, and driver's Rp is relatively low.
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