Tube Amp settings: Triode vs UL; 8 ohm vs. 4 ohm ?


Hi. Advice please. EL-84 tubes. Cary Rocket 88 tube Amp. Klipsch Forte 8 ohm speakers. 
 

I can Triode Class A this amp, or A/B it on UL?

I also am blessed with switches for Ohm: 4 or 8?

 

Speakers efficiency is upper 90’s db

What is the decision process for settings? 
 

128x128moose89

I also have those options on my tube amplifier.  In addition to output tube types, and variable feedback/damping. I view it as a wonderful opportunity to explore my personal preferences. Other than the fact that the output tap used will likely be more driven by the impedance of the speaker across the frequency range.  

Utralinear uses a very specific point on the primary winding where the screen tap is placed in order to get the best linearity- in which case the linearity curve looks like any DHT triode.

For triode operation the load on the tube changes (usually has to be lowered) since the plate resistance of the tube decreases. The chances that the correct load is present for triode operation and the correct location of the screen taps is present at the same time seems unlikely- I would expect one or both to be a compromise.

So I don't think you can say with any accuracy that one or the other is better in some sort of general way. You'll simply have to listen and see for yourself. But if you like what you hear with the triode setting, I would consider getting an actual triode amp.

@atmasphere 

So I don't think you can say with any accuracy that one or the other is better in some sort of general way. You'll simply have to listen and see for yourself. But if you like what you hear with the triode setting, I would consider getting an actual triode amp

Agree and this is exactly what I ended up doing. 😊

Charles