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Pentode Power Tubes - Ultralinear vs Triode

While I’ve seen a bunch of posts on power tube rolling, I haven’t seen much mention of how preferences correlate to what mode you run if your amp has that option. I have a Primaluna DPHP that has the Ultralinear/Triode mode remote and can run a bunch of EL34 variants up to KT150.
So far I’ve only tried the stock EL34 and Tung-Sol 7581A and seem to prefer Triode mode with both. Before coughing up for another set of 8 to try I’m doing more research. I think based on my preferences so far that the bigger, punchier tubes may not be the way for me to go. I could be destined to find my way into SET amps eventually.

So which tubes do you prefer in what mode of operation?
cat_doorman

Showing 2 responses by jjss49

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jjss49
6,612 posts
 
i would concur with others that the modern russian kt77 labelled gold lion genelax (gold and red box) is pretty much the best sounding current el34 variant

good linearity and drive with a fair dose of tubey magic 
jjss49's avatar
jjss49
6,612 posts
 
op

answer to your question is totally dependent on speaker and its load to the amp

triode mode reduces output 3 db which is substantial on some lower sensitivity speakers and also changes the power tubes' 'leverage' into driving the speaker

so as is the case in many of these questions, you can really only try for yourself and see
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