Ultralinear and Triode. What's the difference

Hi Philefreak. My response to you was not meant in any derogatory fashion, and I apologize if it came across as such. (I re-read my response to you and cannot figure why I got such an insulting response from Jeffry)

In my response to you I simply wanted to state that by triode strapping a pentode you do not compromise the tube in anyway, in fact no matter how you configure it, it still runs as a pentode/tetrode.

A pentode/tetrode needs to have it suppressor and screen grid biased to +. There are basically three ways to do that. You can bias the grid from the power supply (pentode/tetrode mode), you can bias them from a center tap on the primary winding of the output transformer (ultra-linear) or you can bias them from the anode (triode mode). Why the latter is called triode mode I am not sure as the tube's suppressor and screen grids still function as designed, and as such the tube is still functions as a tetrode/pentode in every respect.

To your point, a triode strapped pentode is not a triode; not by a long shot. (But I cannot see where I supposedly had said anything to the contrary)

It is however, quite handy to have the triode vs. ultra linear switch as allows you to slightly alter the characteristics of the amplifier. As such you can change it to suit the music you play. Most audiophiles normally prefer pentodes to be triode strapped. Personally I prefer pentode/tetrode mode, but I have rewired a number of peoples tube amps to triode for them.

As for pentodes or tetrodes being inferior to triodes, well that is plain ignorance. Most pentode/tetrode amps have cheap components and cheap output transformers. As such they are unimpressive. However, if you ever have the opportunity to hear an amp like an Art Audio Gill (single ended triode strapped EL34) or AudioNote 6550 SE (single ended tetrode) you'll forget any notion of pentode/tetrode being inferior. They can provide fantastic sound given the right design and components that exceed true triodes in some areas.

“I'm going on my sound preference alone, not a debate over tube topology correctness. “

That makes two of us.

Regards
Paul

Saki70, I did not make any negative statement about the parts Cayin uses, and I categorically deny that as it would be a silly remark. I have been at the Spark factory in China and Herman or PrimaLuna representatives are there for weeks on end, and in fact Primaluna and Herman have bought a residence very near the factory.

Cayin and Spark's design are done to their standards they buy parts like any other business. The people at the factory took me on a tour of the area and treated me like family and to an incredible standard

PrimaLuna is different than Cayin. PrimaLuna are designed ground up in Europe. PrimaLuna has features that can't be found on any product, like Adaptive Autobias, our new CD player with a vacuum tube clock, and the transformer designs.

The whole operation could be moved to another factory at the drop of a hat if we felt they were not maintaining standards that Herman and the PrimaLuna heads in Holland felt were needed.

I did say this....and it is true. The range of work you can have done in China ranges from crap to some of the best in the world. The Gold Peak factory is like a city and builds stuff for the largest companies. From the biggest battery names to pro music gear in the hundreds of thousands of units.

The one thing that is true is this:

In most Chinese factories they will change out parts on you in a minute if they run put of the one you spec'd out for. They may do it because theu think it's going to help you or because they make ten cents, or they don't want idle hands even for ten minutes.

I have sold the earlier Chinese products. Note the operative word is "sold" I'm not the kind of guy that needs to do anything for a buck. And in fact our business now allows us to walk away from anything that I feel is wrong or dangerous for my customers to own.

I have seen prducts where the schematics that came with the amp didn't match the gear. Out of a 5 watt resistor? It will probably work with a one watt value. The feeling in the culture there is to get the product out. Now.

When the TAS Golden Ear award winning PrimaLuna ProLogue Three preamp came out, Herman asked the Chief Designer in Holland to one more time to measure all the components for heat. Everything was great, the unit met CE standards (more difficult than UL here in the states), but one voltage regulator was hotter than they liked.....but legal. I thnk most people would have said "let it go" because frankly, we wanted them ASAP.

Herman stopped it and the change due to that caused a 90 day delay. But we don't want it to be "O.K."

We want it perfect.

Upscaleaudio ;
I fail to see where I stated that you made a negative statement about Cayin's parts ! Perhaps you misunderstood my comment . What I stated was what you told me and what you stated in your reply !
"Cayin and Spark's design are done to their standards they buy parts like any other business."
"In most Chinese factories they will change out parts on you in a minute if they run put of the one you spec'd out for. They may do it because theu think it's going to help you or because they make ten cents, or they don't want idle hands even for ten minutes. "
"I have seen prducts where the schematics that came with the amp didn't match the gear. Out of a 5 watt resistor? It will probably work with a one watt value. The feeling in the culture there is to get the product out."

I then reiterated what you told me about Primaluna as you eluded to .
"I have been at the Spark factory in China and Herman or PrimaLuna representatives are there for weeks on end, and in fact Primaluna and Herman have bought a residence very near the factory. "
And
" The whole operation could be moved to another factory at the drop of a hat if we felt they were not maintaining standards that Herman and the PrimaLuna heads in Holland felt were needed. "

I have worked in the medical supply field for many years . I am quite aware that some manufacturers use the cheapest available parts in their process , to save part of a penny per unit , and of a few that will not allow this practice in order to maintain quality control and reputation . This is a reason for the many recalls that we see today . What you told me , and what I reiterated above , is quite well known in the industry and is not derogitory in any way .

I fail to see the reason for your concern , your above post or email to me after two months. However misunderstandings do occur !

Good luck .

Bringing back an old thread for my first post here!
What a way to say hello lol...
For a quick primer, I decided to fall into this audiophile black hole. Had a few wake up's and is something I have always wanted to explore.
My tumble into the abyss started just about 1 year ago. Had a few drinks which gave me the courage to make my 1st purchase (Elac's... Loved them, but upgraded already) My second purchase was the Yaqin Mc13-S. (Upgrade path in progress ;-) ) Have been learning every day, doing DIY (ACA, Elsinore's) and I'm pretty much a gonner!

My question... I hear many talk about UL/Triode mode for SE amps, but have only come across one page/post mentioning this for push pull setups. Looking at the MC-13S schematic I see its wired in UL on all 4 tubes...  Pin 4 or the screen of the EL34B's comes straight off a tap (not sure if its 43%).. but the topology looks similar enough to many popular DIY amps that it might work...  

My question, before I tear into a working amp (and dont yet have my new one) is will the differences between the to modes be less noticeable in a push pull  ??
For the price of 4 100ohm resistors and a switch, it seams silly to not add the mod if it works... Can only imagine its not mentioned anywhere as you guys who know this stuff would prefer to spend on parts and build yourself something proper.... 

Glenn

Yes, an old thread, however  great one! I bought a used Line Magnetic 211ai which is EL34 output based and runs in triode and ultrlinear. I just received it and played in in UL yesterday. Going triode today.  I bought it for exploration. Wanted to hear the difference between modes of operation and also to see how a lower watt tube amp can drive my Tannoy Sterlings.  I have heard the Line Magnetic 845 integrated amp which was lovely. Should, after discovery, I choose to I will likely sell the LM211 for a more upscale amplifier. In the past I didn't have the resources to explore my passion in audio. Now that my wife and I am retired and have put 3 kids though college, one each BA, MS and PhD, we can direct funds toward our hobbies.