Output tube life expectancy in Triode vs. Ultralinear mode.

Wondering if one might expect longer tube lifetimes in triode {in ST-120 and M-125} due to the halving of output in triode???

Kentley wrote:Wondering if one might expect longer tube lifetimes in triode {in ST-120 and M-125} due to the halving of output in triode???

I don't think so. You still have the same current and power losses within the tubes.

"I don't think so. You still have the same current and power losses within the tubes."

That certainly makes sense. So much for wishful thinking.....Thanks, Peter.

I don't like the sound of triode mode, myself. Perhaps its dependent on the type of music.

Tube Nube wrote:I don't like the sound of triode mode, myself. Perhaps its dependent on the type of music.

Triode/Ultralinear preference is not only highly subjective, but also undoubtedly highly system-synergy related. Technically, as I've read, ultralinear is lower overall in distortion and wider in frequency response. That said, it isn't necessarily "better" in your system with your music pumping into your ears. Remember -- all music-reproduction eqiupment involves a complex series of compromises. Something as slight as a change in rectifier can change the entire soundscape. I'll shut up now.

No, no, Thanks for that!

The most notable thing I hear is the loss of output power--no problem there the volume knob cant resolve. Next, though, is the almost as obvious loss of detail. Muted fidelity, is how I'd characterize it.

Though I do think that might help matters on my Carpenters record. I can't say why birds suddenly appear, but I can say that when those horns suddenly come in, too loud and brash, it's unpleasant.

Ahhhh Karen Carpenter. What a voice. What a tragedy.

Karen in triode mode was a fine singer. However, in ultralinear she was, unbeknownst to many, a superb drummer. Go figure.

Seriously, tubenube's observations are perceptive. Here's what I've found just recently (trial-by-error, as usual). ST-120. Weber WS-1 SS recti.
The increase in B+ is significant. Bias pots must be lowered quite a bit. With the extra "oomph" triode mode sounds more natural. Evrything is a give-and-take. BTW in my situation, the AC mains voltage is 116-118 VAC. That leaves me currently {har har} with a B+ pretty much in the middle of the range recommended by Bob of 370-410 (approx. 390). It's a complex world.....

Bob just put his wisdom in the mix. His points are well-taken.

Say, maybe that's something for me to try...

Kentley wrote:Karen in triode mode was a fine singer. However, in ultralinear she was, unbeknownst to many, a superb drummer. Go figure.

Seriously, tubenube's observations are perceptive. Here's what I've found just recently (trial-by-error, as usual). ST-120. Weber WS-1 SS recti.
The increase in B+ is significant. Bias pots must be lowered quite a bit. With the extra "oomph" triode mode sounds more natural. Evrything is a give-and-take. BTW in my situation, the AC mains voltage is 116-118 VAC. That leaves me currently {har har} with a B+ pretty much in the middle of the range recommended by Bob of 370-410 (approx. 390). It's a complex world.....

Bob just put his wisdom in the mix. His points are well-taken.

Hi Kent...Happy New Year to you and your family...and to all here on the forum!
Not exactly the subject matter here but it is part of the mix. I have been putting off for some time introducing 2more output tubes into my m125's...not for power but the extra "oomph" for my translation means an increase for mid-range and tweeter performance. I have heard that the introduction of the additional output tubes would only increase bass response.
Personnly, I don't know but I think this week I will do some listening with a lot of observation...in triode mode....always.
You can only push the envelop so far...sometimes I think we all get a little anal to think changing a tube here or there will make all a dramatic difference and we seem never to be content with the obvious..."it perfect as it is"..."don't fix what is not broken"...but then this why this hobby never peaks!

Thanks, Mr. Meanies. Greetings to you and yours.

First, it is difficult to predict what potential one might unlock from adding the full complement of output tubes in your particular circumstance. By all means, go ahead and try it. You will not be wasting anything, as these new tubes would serve as backups and be used eventually.
I'm sure you know that a doubling of power won't give you twice the volume. It might be a few db, just as it is when one switches from triode to ultralinear. The reason why the general wisdom is that the increased "beef" will influence bass more than mids and highs is simply that the vast majority of power is used to reproduce bass. Also, remember that, under reasonable listening conditions, you are undoubtedly using only a fraction of the potential of those M-125s.
Knowing your specific listening environment through audiobill, I might suggest once again that you will get much more cleanliness in your mids (particularly) if you redefine your acoustic space. Get those speakers away from the outer walls! Or treat the walls so that they "disappear" from the equation! That will clean up your sound much more than any alterations you could make in electronics.
Keep in touch. We do have much in common vis a vis our equipment and our listening rooms. And we're both OCD old farts.

Bob, I just spent 45 minutes scanning the articles you posted on "Utralinear" mode, and, though my tech comprehension is fairly low, I gleaned enough to begin to understand how this all works and what it means to the listener. I see that ultralinear is an ingenious use of negative feedback to control a pentode so that it sometimes acts like a triode. A "best of both worlds" scenario.
Becase, as you deftly summarize, UL is a more efficient way of using the same voltage to produce higher output, perhaps the opposite to my original theory might be true - that UL may actually be more conducive to long tube life than triode, not to mention less stressful on the entire circuit. Anyone care to comment?

I find that triode mode is quite tasty for laid back jazz and soft instrumental ...

I've been known to roll with either when I'm feeling laid back and soft ... which ain't all that often ... ROCK ON!!

PS ... If in triode, I actually prefer it at lower wall current using the bucker. Then again, UL may lose a bit of punch at 116vac, but it more than makes up for that in low bass definition ...

In any case, nice to have the option available.

Tough call. I think it's a Ford-Chevy thing. And yes, it is nice to have the option. I use Pentode mostly and like it just fine for low-volume listening. Probably depends on your speakers and preamps and other inputs.