Ultralinear and Triode. What's the difference


What are the tonal differences between these two modes of operation?
gnugear
The way I hear it on my Cary SLI-80 is that the triode mode is softer, with less frequency extension, the edges are rounded off, the midrange is slighty more pronounced, less bass control and other things related to those issues. I like UL on most music truthfully, but some others like only the triode. Of course, whether you like one or the other has to do with you, your room, and your other equipment. Are you thinking of a specific piece of equipment? Maybe someone can chime in that actually has one?
Rush
Looking at the newer Primaluna integrated amps, there's an option for switching between modes on the fly. Just wondering if it's worth the upgrade.
Are you aware the Cayin A-70t, and the PrimaLuna integrated amps are both made by Zhuhai Spark Electronic Equipment Co. LTD in China? The Cayin A-70t has similar features and 47% more power for $500 less than the PrimaLuna DiaLogue Two.
This'll be a bit of a generalization, but here's my impressions based upon experience; Ultra-linear will yield more power and punch, at the expense of holography. Triode will sacrifice the power for a greater sense of dimension, space and textural nuance. Ultra linear leaves me with the impression of sitting much further back in the performance, while triode brings me in closer and gives me a better sense of where the instruments are on stage. If my tastes were in hard driving music like Rock, I might like the muscle and drive of the Ultra-linear. My preferences tend towards acoustic, vocals, folk, blues..more subtle, sparse arrangements in general, with more detail and nuance than most driving rock. I've found for my tastes I prefer Triode. When I had an amp that gave me the option to switch, I almost always ended up listening on triode. No experience with the amps you are considering.

Hope that helps.
I believe most with golden ears and even the audio writers that critique equipment for a living will tell you triode is where the real music happens.
Gnugear ; as stated earlier , it depends on what type of sound that you desire . Personaly I prefered ultralinear for my rock and blues music . It just has more oomph ! (How is that for an audio term ?)

It is corerct that the two amps , Prima Luna and Cayin , are manufactured by the same company .
But that is where the similarity stops !
It is my understanding that Prima Luna dictates the parts that are to be used where as Cayin farms it out to the lowest bidder . Also , there is supposed to be a quality control rep , from the Prima Luna company , overseeing the production process .
Sales hype or not ? I don't know . However having owned both , the Prima Luna Prologue 2 and the Cayin A 88-T , they do sound quite different from each other !
Thank you, that was very helpful.
However having owned both , the Prima Luna Prologue 2 and the Cayin A 88-T , they do sound quite different from each other !
Saki70 (Threads | Answers)
Would you mind describing the differences? Were you using them with the same ancillary equipment and loudspeakers?
Triode mode is simply using the more liner part of the tubes amplification ability. The cost is about one half the power. The only reason for ultraliner is to try and get more power from the circuit. No engineer ever claimed that it was more liner (i.e. sounded better)
The most likely reason that anyone would prefer an ultraliner or tetrode configuration, is that they simply need more power in the particular application.
To really hear what triode is all about. You need a tube amp that uses triode tubes! Pentode tubes that are in a circuit that gives the ability to switch from triode to ultalinear does not really let you hear what triode is all about! In these type amps, almost always the ultralinear mode will sound better than the triode because the pentode tube is in a circuit that makes compromises for the flexabilty.
Philefreak ; very informative , I was not aware of that ! Just for my info , can you list some common examples of pentode tubes and triode tubes ?
Man I love this forum !

Tvad ; the two integrated amps were used in exactly the same conditions .
If you have heard the Cary SLi-80 you will know what the Cayin sounds like . I A/B'd them and could not justify the added exspense of the Cary . I am relatively new at this but would describe that sound as traditional tube . Warm mids and rolled off at the extremes . Given that Cayin outsources their parts to the cheapest bidder , it is quite possible for one batch to have a slightly different sound than another batch due to the varying components used .
The Prima Luna , on the other hand , has much better extension especially in the high end . The lows are a little better and the mids are not nearly as warm . The P.L. also shows more detail with a greater amount of air and resolution .
I would really like to get the warm mids of the Cayin incorporated into the P.L. , kind of like the best of both worlds !
I intend to call K. Deal to see if that can be accomplished by rolling some different tubes . I don't want to loose any of the other attributes though .
I hope that this helps .
Thank you, Saki70. May I ask you what is the source of your information regarding Cayin outsourcing parts to the cheapest bidder? I'd like to read about this.
I can give just a few cause I don't know all the tubes that are out there! Pentodes- EL 34,KT 88,6550,most pin guided sockets are pentodes or tetrodes. Triodes- 2A3,300B,45,PX 25,845,6C33,6AS7,etc. some of these have a 4 pin socket. My favorite amp is a Push/Pull 2A3 triode using 6SN7 as an input and driver tube. It's only 18 watts but, on my 91DB flat 4 ohm speakers it's plenty!
I was given this information by Kevin Deal at Upscale Audio . He is the N.A. distributor for Primaluna .
I was given this information by Kevin Deal at Upscale Audio . He is the N.A. distributor for Primaluna .
Saki70 (Threads | Answers)
The distributor of PrimaLuna is commenting on the parts content of a competing product. Understood. Thank you.
Philefreak, KT88 and 6550s are tetrodes. The “KT” stands for kinkless tetrode. The screen and suppressor grids are tied, hence being a tetrode. An EL34 is a true pentode.

Running a 6550 in triode mode simply means that the suppressor grid is biased to the anode, normally via a resistor. It does not compromise the working of the working of the tube or the sound in any way. The suppressor and screen grid do not “get in the way” of the functioning of the tube when run in triode mode. Most audio critics/audiophiles prefer pentode and tetrode tubes wired as triodes.

Regards
Paul
Tvad ; as I stated in my first response , "Sales hype or not ? I don't know ."
Please report here , or p.m. me , with the results of your research . It could be quite informative , in more ways than one !
Thank you .
The CAT JL2 uses a pentode tube (6550) in triode mode. I don't beieve there was any compromise made in choosing tridoe operation. It is one of the best sounding amplifiers I have ever heard. I suspect that design and implementation may count for more than design topography.
My my, half-truths and overgeneralizations.

Pauly: Running a pentode/tetrode in triode "...does not compromise the working of...the tube or the sound in any way." I'll agree with the 'working' part, but the 'sound' part I disagree with strongly. I believe most hi-end audiofools would state that true triodes almost always sound better than triode-wired pentodes/tetrodes (P/Ts). That's why virtually no Single-Ended Triode amp is made with KT88s or 6550s or EL34s or any other P/T. The VAST majority of builders and buyers of SETs build and buy them equipped with real triodes such as 45s, 2A3s, 300Bs, 845s, or 805s*. Probably most push/pull triode amps are designed with P/Ts for some reason. Maybe that's because once one departs from the sonic purity of an SET, it matters less whether one uses a P/T or a real triode.

Pauly: "Most audio critics/audiophiles prefer pentode and tetrode tubes wired as triodes." Really? My understanding is just the opposite.

I believe that triodes get the harmonics of the music better than do P/Ts. I'm now on my 2nd pair of mono SETs, this time with high-sensitivity speakers, DIY open-baffle linearrays, and I have NO plans to ever consider going back to tubed amps using P/Ts.
.

* The typical output power of these class-A triodes used in SETs approximate 1, 3, 8, 20, and 40 - 50 Watts, respectively. I'm not familiar enough with the PX25 and 211 to state each's typical power output in an SET.
.
The term ultra-linear is also called "distributed load amplifier" wherein the sceen 2 of the tube is DC biased from each half of the primary such that the tap point is 43% of the turns ratio or 18.5% of the impedance when measured from the primary center-tap.
Both the KT88 & 6550 are often used in the ultra-linear configuration for power amps because, I understand that, these 2 tubes (not the only ones, mind you!) are physically constructed such that the above mentioned percentages can be obtained. I also understand that the EL34 is a tube made for correct ultra-linear operation.
Technically speaking the ultra-linear amp delivers ~2X the power of a triode amp & about 75% of the power if the same tubes were used as pentodes using the same DC voltages with substantially less distortion.
Sonically, the ultra-linear sound is supposed to be (generalized) "clean, bright, sharp, punchy" sound while the triode sound is supposed to be (again, generalized) "smooth, sweet, mellow, natural" sound.
01-19-07: Jeffreybehr "... but the 'sound' part I disagree with strongly."

preference in sound is 100% subjective and as such rather stupid basis for an argument.

"That's why virtually no Single-Ended Triode amp is made with KT88s or 6550s or EL34s or any other P/T."

Really? I happen to own a SE ASL KT88 triode and an acquaintance owns a Art Audio Gill Signature. I guess those two are anomalies? Or perhaps you are the one generalizing?

"The VAST majority of builders and buyers of SETs build and buy them equipped with real triodes such as 45s, 2A3s, 300Bs, 845s, or 805s*.

The vast majority of builders and buyers build and listen to transistor amps. Doesn't mean that's to everybody's taste, does it?

"Probably most push/pull triode amps are designed with P/Ts for some reason."

Wow, really? Funny, I own a SE 6550 Audionote wired in tetrode mode which sound just great. Should we call Peter Qvortrup and tell him he is a dummy for designing such an amp?

I must have build about 20 tube power amps and there is nothing that makes a triode more (or less) suitable for a SE application than a tetrode or pentode.

[Most audio critics/audiophiles prefer pentode and tetrode tubes wired as triodes]
"Really? My understanding is just the opposite."

Just about every review of an amp with a triode vs. ultraliniar switch, the reviewer has always preferred triode mode. You should try read some reviews.

“I believe that triodes get the harmonics of the music better than do P/Ts”

LOL, they “get” it better, do they? Yep, I am out of my league attempting to argue with my limited knowledge.

“"I'm now on my 2nd pair of mono SETs, this time with high-sensitivity speakers, DIY open-baffle linearrays, and I have NO plans to ever consider going back to tubed amps using P/Ts.”

Bully for you.

"The typical output power of these class-A triodes used in SETs approximate ... blah blah"

FYI , it is somewhat redundant to say “ class-A triodes used in SETs” as any SE amp has to run class A. Also, there is no such thing as a class A triode. Class A refers to how the tube is used. Any triode can be wired in class A or class B. Thought I'd let you know.

Regards
Paul
"preference in sound is 100% subjective and as such rather stupid basis for an argument" Then why argue? Your vast knowledge is impressive but, your the one that insist upon setting myself and Jeffreybehr straight. All I suggested is that I've never heard a pentode,tetrode(no matter the topolgy) sound like a true triode done class A. It's a sound preference thing that isn't worth argument. Kind of like an analog/digital, tube/solid state thing. I'm just giving my opinion to the original poster. I think that he or she may benefit from my experience. I'm going on my sound prefrenece alone, not a debate over tube topolgy correctness. Not worth an arguement!
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 .