I hate to say it, but now I think maybe I like my amp in ultralinear mode versus triode

Yes the link was very helpful. It's good that I am very intelligent and can understand these things. Thank you

Yes, that is good.  I am happy for you.  But do not thank me; thank @atmasphere ,  as he posted the link a few posts before you said you would like to see a diagram.

@audphile1 , I felt as if the instrumental work  (as I typed, particularly what was in the center) had a bit more texture and therefore was bit more palpable sounding when I switched over to ultralinear.  This was after listening to the same (instrumental) "Jazz Essentials" CD twice in a row.  After switching to UL I listened to most of it for a third time and I felt as if the instruments had more "bite" (if that's the right term).  

As far as vocals, I didn't start listening to music featuring a human voice until after I switched to UL, but vocal work is mostly what I do listen to, and in UL the voices seemed closer to me than I remember them sounding in triode. (Cary claims it is okay to switch that amp around "on the fly", so I guess I could have done that, but I didn't).   Anyway, I prefer the "up front" presentation, so today it was working.

But who knows with my bipolar hearing . . . tomorrow I wouldn't be surprised if it all   sounds like hammered dogcrap in UL; but for now it is striking me as a bit of a sonic revelation.

The only thing I can think of, your amp is more effortless in ultralinear?

@grislybutter , I was thinking along those lines myself. The Revels (sensitivity 86 and minimum impedance 4.7 ohms) are supposed to be an easy load to drive (according to the reviews) and I didn’t think that the amp was straining in 50 wpc triode, but maybe it was and I didn’t know it.

@audphile1

It’s not night and day but enough to hear.

Yes! That’s the way I would describe it. I still haven’t tried A/Bing those PCs from Amazon, the Preffairs (sp?), but if there was a difference with those, it was subtle to the point that my untrained ears were unable to detect it. With that typed, my ears are not that great (and those PCs have been in the system for a while now, so now maybe I would). However, I immediately heard this today, as in immediately, and although it didn’t sound like a whole different component, if I could hear it, with my ears, that says something. As I typed previously, today I liked it.

@artemus_5

not sure why you "hate to say it" that UL sounds better than Triode.

Well, I guess because for nearly 23 years I steadfastly maintained that triode sounded more refined and also "more better." Perhaps I was wrong about "more better."

@tablejockey

Your hearing isn’t as sharp as it was. Now UL is needed to "push" instrument passages closer to please the ear. That’s my personal diagnosis as hearing degeneration and tinnitus take over.

"In UL the voices seemed closer to me than I remember them sounding in triode."

My experience toggling between the 2-

Triode-instrumentation is pushed back with vocal taking center stage.

UL- instruments pushed forward just behind vocals.

I am willing to concede that my hearing is worse now than it was when I bought that amp. And considering that I spent a lot of my adult life around jet engines and hammering rivets with inadequate hearing protection, I often wonder how good it ever was back when I started my personal quest for "better sound." Your description of UL versus triode I think is what I was getting today. I’ll pay closer attention tomorrow.

@decooney , I was meaning to ask you about your feelings of triode versus UL with your V12.

@mulveling

There’s some paranormal audiophile force that makes us feel like the more "purist" approach must always be better:

I guess I had fell into that. The power of suggestion, perhaps?

Don’t confuse UL with "Pentode" mode.

I readily admit to how illiterate I am when it comes to electrical. Actually I had always thought that the one was a synonym for the other. I am in need of an education. Can you put into layman’s terms the difference between the three? If layman’s terms just won’t work because the subject matter is just too complex and it would take writing a book, I understand. I can live with just knowing that today I liked UL better today.

As an aside, the subject of the Mesa Baron amp (from the late ’90s) came up on this forum a few days ago. I actually took one home for a weekend, and I still have the Stereophile issue that reviewed it, and I am going to dig it out in the morning because I cannot remember if they said that it was switchable from triode to UL or switchable from triode to pentode. At the time I posted to that thread (the one I just alluded to) I was thinking they were saying pentode, but now I’ll have to look. The dealer who let me audition that amp said that the popular setting was 1/3 triode and 2/3 UL or pentode (as I just typed, I am not sure which). Anyway, at the time I was listening to my little Cary SLA70 and the difference was dramatic. The Mesa Baron literally filled the room with sound stage and put vocals right in my face. I thought it was pretty neat. I described the sound, shortly after, as "musky or smoky"; I remember that Margo Timmins’ (Cowboy Junkies) voice sounded kind of husky, which it usually doesn’t. But during the audition, it didn’t have a negative effect on me. The last thing I did, however, the Sunday night before I had to bring it back or buy it (and I was pretty much set on buying it) was to hook the Little Cary back up and I listened to the Cowboy Junkies cover of Sweet Jane either off of Trinity or their only (at the time) live CD, and it was then that I understood the meaning of "black background." Cymbals shimmering and hanging in the air. The Mesa Baron did not do that, and even though the sound stage, such as it was, shrunk to around the speakers with the Little Cary, I decided that it was not a good trade.

Anyway, I’ll dig that review out tomorrow to see if they referred to the Baron as switchable to UL or switchable to pentode.

@decooney 

@immatthewj you were pretty close on your thoughts and memories of the Mesa Baron amp. Appears that amp delivers 150Wpc in full pentode mode, 120Wpc in 2/3 pentode, 85Wpc in 2/3 triode, and 60Wpc in full triode.

Ask: so, which of the switch modes did you enjoy most with the Mesa Baron amp?

If I may suggest, there might be a "next chapter" for you in your discovery, possibly moving to now try a (non-switchable) dedicated Ultralinear amp(s). Then trying a dedicated (non-strapped, true single ended) Triode amp with actual Triode tubes. 

I found that issue of Stereophile, and what a looker that amp was!  Dual monoblocks in one chassis, rack handles, meters, switches, knobs, a dozen output tubes . . . that, unfortunately, was probably a lot of the reason I was initially intrigued with it.  (A guy I used to work with used to say I was like the Indians who sold Manhattan for some shiny trinkets.  He may have been somewhat correct.)  Anyway, Anyway, I also found the flier from Mesa for The Baron that the dealer gave me (I had the flyer inside the Stereophile) and Mesa was saying that the amp utilized "pentode."  As far as which mode I preferred, well, I spent very little time in full triode or full pentode, most of the weekend was spent in 1/3 triode 2/3 pentode per dealer's advice, and I actually was intrigued and initially liked the presentation until I did the A/B I typed about.  At the time, I was using a B&K digital HT (prologic back then) preamp, and I had a dealer in Philadelphia who had set me up with that first system (the B&K and the SLA70) and I talked to him about the experience and maybe upgrading to a pair of SLM100s to get the sound stage without the "smokiness" and he told me (and I will have to paraphrase) that 'the Baron is a chameleon'  I do remember he did use the word "chameleon" and the sound I heard was due to the level of preamp.  Which may have been true.  But I didn't buy SLM100s from him.

What I did do not a whole lot later was to buy (through the classifieds in the back of Stereophile)  a secondhand pair of ARC VTM120s, four 6550s each, 100 wpc in NONSWITCHABLE UL.  And I like those ARCs, I really did; they would rock out (and I mean ROCK OUT) or whisper . . . and it was CLEAN sound and that was with the B&K in front.  And then, another aside, but still another local dealer had a second hand modded SLP90 that I took  home for a weekend, and then and there I learned the difference a preamp can make.

The reason I didn't keep those ARCs (I still have the SLA70, btw) is that they had a random habit of blowing a grid resistor on start up.  And taking one of them down and desoldering and resoldering grid resistors is no way to start a listening session.  I used to grit my teeth and cross my fingers when I flipped the switches.

Anyway, when Sterophile reviewed the V12 I was intrigued by the switchable from triode to UL feature and I knew that back then (in the Dennis Had/Kirk Owens days of Cary) I found my SLA70 to be reliable and Cary's tech support (when needed) was superb, so I took the plunge and bought a V12 from a dealer in Colorado, sight unseen.  

And that's how I got to the V12.

Thanks for the great post, and with your V12, did you roll any tubes besides the EL34s?  Like 6550s for example?  I do note that in the owner's manual, Dennis Had was saying one could do that.  I have about three good quads of 6550s for my SLA70 (six of NOS Tung Sols 6550 from Andy in Michigan, a quad of Svetlanta 6550Bs,  and I think a quad of KT88s, but I'd have to look to be sure, hat were branded "Tesla" that I got from Audio Advisor).  I was thinking of possibly biasing the amp for two tubes aside someday, and trying it in UL with 6550s?  I tried four tubes aside once back in '18 or '19, but I have to confess that this was back in the days when I was swearing by triode, and I wasn't crazy about it.

I was just pulling your leg. Its a bad habit I have.

@artemus_5 , you asked a legitimate question--I didn't take any offense to it.  After all the time I spent swearing that triode was a superior sound, I hated to admit that after yesterday I feel that I may have been mistaken.

@ozzy62 , I will say that reading what the owner/operators of SETs have written about the experience has always sounded intriguing, if not tantalizing.  I sort of have a fantasy about higher efficiency speakers and one of Dennis Had's Inspire setups.  But that ship has sailed for now.  Maybe that is why I was so dead set locked in about triode versus UL--I thought it would be the next best thing?  Maybe.

@frogman your perception of triode versus UL is also interesting.  I suppose the possibility does exist that I am preferring UL at the moment in my sweet spot is due to it being different.  Different is often exciting.

@viridian 

It says right in your owners manual that the designer, Dennis Had, preferred the amp in triode, for whatever that is worth.

Yes it does!  And that may be where the power of suggestion comes in to play and why I was previously unwilling to give UP any serious time beyond ear-bleed rock-out sessions.  I also hate to admit that it was probably Dennis Had who turned me into a fan of Female vocalists.  The power of suggestion again.

@freediver 

I do however believe this is speaker dependent

possibly, and up until this spring I was always using the V12  in triode to drive a pair of B&W 805 Matrixes.  

@elliottbnewcombjr 

I remember a convesration we both particiapated in about someone's SLI80.  I believe you made a reference to face slapping when I stated I preferred my V12 in triode.

@mulveling , thank you for taking the time and effort to type out that explanation. I am going to print it and try reading it slowly and thoroughly to digest it. I think that you probably did a good job, I struggle with electrical. When I was in HS the Air Force recruiter told my mom that I did "real well on electrical on the ASVABs." I don’t believe that he was telling her the truth. When I finally did go in a year later, they were, "Sorry, son, electrical is full--how about open mechanical?" (Meaning airplane grease monkey.) Probably a good thing electrical was "filled up." I doubt I would have been good at it. Anyway, I think you are right about "better than death."

@atmasphere , thank you also for the explanations. I was pretty sure you would have a handle on this stuff. I now wish that I had gave UL a SERIOUS whirl (as opposed to the short try outs or ear bleed sessions) before this. Not that I didn’t like my amp in triode, but now I am thinking it is "more better sounding" in UL. Thanks again for the feed back.

It's always a pleasure to read about a fellow hifi enthusiast who has owned and enjoyed decades of music through their gear!

@jimmyblues1959 , it's been "a long strange trip . . ."  (Not really, but it was fun to say.)  

@silverfoxvtx1800 

wow!  I had a pair of ARC VTM120s that intermittently blew grid resistors on start up.  And I thought that was bad!  Those ARCs were pussy cats and replacing grid resistors was a minor inconvenience compared to what you just described.

@atmasphere 

which is why you can't use the same output transformer with EL34s and 6L6s unless there is a tap for each tube type.

I am not arguing with you because I have already admitted that I am rather cluelss about how this stuff works,

but in the manual for the V12, Dennis Had is saying that tubes that can be roled in this amp include;  6L6, KT88, 6550, KT90, KT66, "even 6V6."

Again, with not intent of being argumentative, does this sound incorrect?  (I was actually asking @decooney  if he had rolled any tubes besides EL34s as I do have some 6550s for another amp, and I can bias the V12 for just two tubes aside.)  Reaching out to Dennis, who is no longer with cary, about an amp he made over 20 years ago is probably a dead end, and as far as this goes, I definitely want to stay on the "better safe than sorry" end of any deal.

I have no recall, was I rude? Mean? I've regressed to teenage behavior?

No, @elliottbnewcombjr , it seemed pretty much made in jest and that's the way I took it.  But I remembered the convo yesterday as I was listening.

The more refined my system has become the more I default to ultralinear especially 

@bolong , and I will say that when I brought this V12 into my system primarily in triode mode my system was less refined that it is today, twenty three years later after the preamp and digital front end upgrades, and possibly the speakers as well.

@emergingsoul , at on or about the 16th reply to this thread, at my request, @mulveling  did provide a description of the different (triode, ultralinear, and pentode) topologies..

@mulveling 

Out of all the possible questions to be asked on this forum, this is one I would never have expected before now. No, UL is not solid state. And it’s about as much a marketing term as "gravity" or "electromagnetism".

You have a way with words.

Yesterday afternoon going into the evening I put five more hours in in the UL mode.  I note a "fuller" presence in UL that I was getting in triode mode.

I won't go  blow by blow into yesterdays session, but I'll mention a couple of things that stood out (from yesterday).  I have been planning (for some time) on listening to to a couple of SACDs (Jacintha Goes To Hollywood and Patricia Barber/Modern Cool) but I never made it past digging out red book CDs that caught my eye and then my ear.  I saw a movie a few nights ago on TV that reminded me I owned Chris Isaac/Heart Shaped World which I bought in 1990 but never listened to all the way through.  Probably over produced for my usual tastes, but the sound was was room filling and it sounded quite good.  I bought Brandy Carlile/The Story quite a few years ago because I heard her sing The Story on my car radio, and I thought that I would like to hear the choruses in which she was literally screaming on my system, which, in theory should sound way better than  the AM/FM radio in whichever vehicle I was motoring about in at the time.  But the playback on that one never met my expectations.  I put in that CD (The Story) yesterday specifically to hear her sing The Story, and I can honestly say that I was struck by the visceral impact of the choruses more in UL than I had been in triode.  I actually wound up listening to the whole CD, and it does have a nice sound.  (It was one of the CDs that kept me from getting to those two SACDs by Jacintha and Patricia Barber, but I am leading off with them tonight.)

However, with all that typed, I will also say that my initial reactions could be the "new toy syndrome"; I am admittedly prone to that infection.  Also, as noted before, my hearing is changing and not for the better, I have introduced different speakers to my system, my system now resides in a different room than it did when I first set it up, and the way I listen has changed significantly over the years..

@decooney , I really liked the sound of my V12 with the Ruby branded EL34s it came with, and I am assuming that those were the same as the Chinese tubes you just referred to.  I don't think that I will be rolling any tube types other than the EL34s.  In an emergency I guess I might try rebiasing to two tubes perside, and trying those old NOS Tung Sol 6550s I got from Andy way back when.  Maybe.

I also remember a couple of conversations we had about biasing that amp.  I di try backing it way down, and I didn't think I liked it at the time.  But maybe that was a preconceived notion I had that low bias couln't be good.  At the moment I have both sides set at just under 270.  As long as I am experimenting with different things, I'll back it off tonight.  I was thinking about 240 mA aside and going from there.  Also, when I last experimented with backing the bias off, I was listening in triode, and triode was another of my preconceived notions that I turned out being open to rethinking.

Thanks for taking the time to replay, you always offer a lot of insight when answering my V12 questions.

@immatthewj Not exactly. But its likely that one tube type in that list will perform better than others. That’s a bit different from saying that it will ’work’; sure it will play but the output transformer should be optimized for a particular tube.

@atmasphere , although I do not understand circuit topology what you write does make sense. I’ve often found that tools that are advertised as fulfilling multiple functions do not work as well as a tool that is designed to perform one specific task. And hand tools are much simpler to understand and work with than circuits are.

As far as rolling tubes, I am not trying to speak for Dennis Had, but from reading the writeups he provides for several of his products (including the V12, from which I sort of recently quoted the manual), I sort of get the impression that he likes tube rolling. I remember reading one of the blurbs he wrote for one of his fairly recent SET amps, and he described it as (I belive the words he used were) ’a tube roller’s dream.’ Anyway, as far as the V12, after reading through the recent posts I am going to assume that it was "voiced" (I’ve read that term elsewhere) for the EL34 and after reading the recent responses on this thread, I am not going to mess around with other tubes. (Although I do have three different quads of 6550s for another amp that I am not using right now, and if worst came to worse, I could drop one of those quades in and bias the amp for two tubes per side). I’d also note that in the manual, Mr. Had writes about the virtues of the triode circuit toplology, and from what he writes about the V12, I am assuming that he includes the V12 in pushpull. Meaning that I guess he probably "voiced" the V12 in triode, but for at least the present moment, I am preferring UL.

@xenolith , I was going to jokingly type thgat you are a buzz-kill, but a lot of jokes are not taken as such. In reality, I wouldn’t be surprised if you are correct. I don’t have much of a grasp on the subject of circuit topology and back when I was setting up my system (the ’90s), I didn’t have a computer and didn’t know about A’gon, and what I learned was from reading Stereophile, what dealers told me, trial and error, and what manufacturers and their tech guys told me when I called them to ask questions about their products.

Anyway, if I NOW had the wherewith all to start completely over from the ground up, I would do a lot of things differently. However, I retired early and I made a few bad life choices before Idid, so I am probably going to find a way to try to be as happy as I can with what I have. But I will add that before the V12 I had a couple of strictly UL products, including a pair of ARC VTM120s which I have referred to previously in this thread, and if they were more relaible than they turned out to be, I’d still own them, and although aural memories (at least mine) are often flawed, going from the ARCs to the V12 was, at best, a lateral move. As far as the sonic presentation, that is. But when I flip the switches to turn the Cary on, I do not have to cross my fingers, and that is worth something.

@atmasphere , I probably used the term "voicing" in error. I probably do not even have a layman's grasp on the subject that we are discussing, but at least I keep a relatively open mind and I am always trying to learn more.  What I meant was that, although I cannot speak for the designer of the V12, was that maybe he probably designed with triode being the optimal mode and the EL34 being the optimal tube, even though he also designed it to be switchable to ultralinear via six toggle switches and that besides the EL34 he lists a few other octal tubes that he says can be used?

As an aside, back in '20 I contacted Jim McShane about retubing that amp, and I had heard so much about the Gold Lion (reissued) KT77 I told him I was interested in them.  He emailed me back and gave me the impression that he wasn't crazy about selling me anything but EL34s for that amp.  I emailed him back and said that 'you know more about it than i do, so if you think I'd be happier with EL34s  than GK KT77s, let's do EL34s.'  He emailed me back and said something to the effect of, 'That's not what I said.  The GL KT77 is a fine tube which I can sell you, but there may be issues with biasing it in that amp.'  Which, with my limited understanding & knowledge of the subject, was good enough for me, and I bought a dozen of the reissued Tungsol EL34Bs from him, which I am still running today.

Anyway, I appreciate the time you take explaining things on this site.  

Does your V12 still have the original Audio1 coupling caps installed in it?

@decooney , no, it came with Jensen caps, and so far that is the only true failure (one of those original caps), and I won't go into the details, but I think that may have been my fault.

Anyway, I think you and I may have discussed this as well; I replaced all four caps and went with the Mundorfs. (I'd have to look at the receipt, but I am pretty sure they were the most expensive Mundorfs that PCX was selling at the time, so "air oil supreme" or something like that, but I'll check the receipt tommorrow and get back to you.  I think I remember you telling me that the caps I picked were okay, but would not have been your first choice.))

@emergingsoul

I think the term ultra linear is marketing in nature and I dare say most people have no clue what they’re buying when they do.

But ultra linear does drift more toward solid state and isn’t that what we’re really saying overall after all

I am not sure whether you are just troll posting, but assuming that you are not, do you also feel that, for instance, single ended triode is also "marketing in nature"?

the differences between modes of operation which on this amplifier tend to be switchable so easily which always raises skepticism

Are you also skeptical about the sonic differences between different vacuum tubes because it is quite easy to swap them out? Adjustable feedback? For that matter, do you believe that possibly the whole concept of vacuum tube gear is also a marketing ploy, and underneath it all lies solid state circuitry?

Just curious.

@decooney , I found the receipt for the Mundorf capsI bought from PCX:  they were the 71552s (0.22 uF 1000 Dc Supreme SilverGoldOil) @ 52.68 each.

A technical reference to triode in marketing literature makes sense, it’s not sexy. Ultra linear Whatever it is that it does is a sexy marketing term. If it’s switchable that’s probably discouraging a lot of people from taking it seriously especially in an amplifier.

@emergingsoul , at this point I am almost certain that you are troll posting. Did you actually read any of the circuit-technical posts from the more tech savvy members?

Here is an article from Wiki that I do not expect that you will bother with, but I’ll post a link anyway:

ultralinear

"Ultra-linear electronic circuits are those used to couple a tetrode or pentode vacuum-tube (also called "electron-valve") to a load (e.g. to a loudspeaker).

" ’Ultra-linear’ is a special case of ’distributed loading’; a circuit technique patented by Alan Blumlein in 1937 (Patent No. 496,883), although the name ’distributed loading’ is probably due to Mullard.^[1] In 1938 he applied for the US patent 2218902. The particular advantages of ultra-linear operation, and the name itself, were published by David Hafler and Herbert Keroes in the early 1950s through articles in the magazine "Audio Engineering" from the USA.^[2] The special case of ’ultra linear’ operation is sometimes confused with the more general principle of distributed loading."

And apparently, if you are not troll posting, you do not believe that switches could be used to toggle between two circuits, even if it was not the optimal way of achieving either circuit?

In audio reproduction, linear is sexy. Ultra linear is ultra sexy.

If you say so; however, neither word strikes an erotic chord for me.

@immatthewj having delt with both of these characters on amps, different tubes, options, I’ll say you are a bit on your own until you partner with a great local tech who can open up these amps and tell you what’s really going on inside of them.  

@decooney , well, okay, but you did tell me that the only tube you wound up using were the Chinese Ruby branded EL34s, right?  At the time I needed to retube that amp, Jim had a bunch of tubes listed in his inventory, including the GLs, which was part of the reason I contacted him for that retubing.  (The last I read he said he was retiring and prior to that wasn't going to sell any tubes made in Russia anymore.)  I was quite happy with those re-issued Tung Sols, and I will say that he gave me what seemed to be better personalized service than any other tube seller I've bought from (with the possible exception some NOS small tubes from of Andy from Michigan).  Jim would send me an email every day or so telling me how the matching process was going, and as I recall, it took a few days or maybe even a week until he emailed me telling me he had two matched sex-tets ready to ship. A couple of years prior to that I had bought a dozen reissued Mullard EL34s from Viva, and it was wham, bam, thank you ma-am, and I had them, but they didn't run long at all (about two years) before the bias(es)  started doing goofy things.

Anyway, as another aside question, did you ever experiment with running your V12 configured in anything but FULL triode or FULL ultralinear?  I mean like 1/3 + 2/3s?  I know that the owner's manual says only run FULL one way or the other, and after the amp arrived to me I talked to Kirk Owens about it, and he didn't sound too crazy about the idea. . . .  I know that the Stereophile review said it was okay, but I always felt better about defaulting to what the manufacturer said than what Stereophile said.  I think I remember that I may have tried it for a real real short time, but I do not remember how I felt about it, meaning it was nothing at all close to as dramatic as the Mesa Baron was.  

@emergingsoul

Ultra linear is a sexy term used by the manufacturer. Cary has not done a very good job to explain it on their website.

ultralinear is a term that is not limited to just one manufacturer, kind of like AC or DC is not limited to any single manufacturer.

I think they’re taking advantage of the technology to promote something that is questionable as to sonic credibility. It’s not a very popular feature. I have never seen it before

I am not sure what you mean by all of this, but just because you have never seen it before doesn’t mean anything. Read the Wiki article I posted the link for. I think it states that the UL circuit was originally patented in 1937. As far as being switchable from one circuit topology to the other, that’s nothing new either. For all the good that it may not have done me, I subscribed to Stereophile throughout most of the ’90s up until ’02 and I’ve read reviews of more than one manufacturers amp that was switchable. What sticks in my mind were a pair of VTL or Manley Labs (I get the two manufacturers mixed up) that were switchable between triode and either ultralinear or pentode. Earlier in this very thread, in a part of the conversation with @decooney , we were talking about an amp called The Baron which was manufactured in the late ’90s by Mesa (dual monoblocks in one chassis with adjustable feedback and a dozen 5881 output tubes); the circuit(s) were switchable between triode and what Mesa was calling pentode, in thirds, and for that, Mesa was using ONLY TWO toggle switches PER SIDE. One switch controlled two pair of tubes, and the other switch controlled one pair of tubes. In other words, both switches could be in either triode or pentode, OR, one switch could have one pair of tubes in triode while the other switch would put two pair of tubes in pentode--OR vice versa. For those who think amps do not make a difference in the sound . . . they should hear the Mesa baron . . . I tiook one home for a weekend and the sonic differences were significant--but not all good. I stayed with the smaller tube amp I was running at the time (another smaller Cary wired in full time ultralinear) and later upgraded to a pair of ARCs (also wired in full time ultralinear) and due to reliability issues with the ARCs (although they sounded fantastic) I bought the V12 I started this thread by discussing.

If you think that the word ultralinear is "sexier sounding" than the word "triode", I can only tell you that if you read Dennis Had’s (the designer of the V12) description of the triode circuit, you might come away thinking that triode is the "sexier sounding" term.

@emergingsoul  wrote:

Again a nice diagram would be nice

@atmasphere  had previously written:

@emergingsoul The term 'ultra-linear' was used to describe the invention that is the subject matter of US patent number 2710312A. You'll see it used in the text of the patent. Its an accurate description of  the time about a break thru in amplifier technology. Diagrams of how it works are at the link.

Again:  

Diagrams of how it works are at the link.

WRT UL, It can be made switchable by having a switch connect the screen of the power tube to its plate as opposed to the tap on the output transformer.

Thank you for that, @atmasphere , that's a nice nutshell that even a layman (at best) like me can just about grasp.

A single-ended amp like the 805 or his Inspires, sure, I can see no global feedback.  But a 100wpc push-pull ultralinear amp without feedback seems like a stretch, in terms of achieving good bandwidth and a decent damping factor.  But anything's possible.  He's a very clever designer.

As far as the CAD-805RS, what Cary lists on their site under specs for feedback is "0 to 10 dB continuously variable control."

Circuit topology of appliances sexy? Someone needs to go on a date....with a human.

@viridian , going on about 25 years ago I was buying some 12AU7s and 6922s for a preamp and amp I had, from Andy from Michigan. I probably made two or three phone calls to get the deal done, but in the course of those calls and conversations, Andy got off the topic of the tubes he was selling me and got to talking about a push pull amp he had recently restored or built (I wish I could still remember his exact words) but it was just a massive amount of class A wpc and when he said something about ". . . liquid fire coming out of the . . ." his tone of voice was almost orgasmic.

Your post made me think of that.

Thank you, @mulveling !  I have printed that as well.

You asked for a diagram, @emergingsoul , it appears as if your wish has been granted a couple of times over.

Yes, @viridian , that was the Andy I was referring to. I enjoyed talking to him. Somehow he got on the subject of amps and the people who designed those amps that he didn’t care for. I won’t mention the names, but as we were talking about the amp, I said (and I do remember this word for word), "well, with the ____ I guess you get a lot of bang for the buck," and he replied with this kind of crazy laugh, "Hoo hoo hoo, or some times just a lot of bang!" And I remember him laughing some more. I don’t know why my memory for certain detail that doesn’t really benefit me in any way is so good, there are subjects that if I could have remembered them as well actually would have done me some good.

@dogearedaudio , I just took a look at the specs listed in the V12 owner’s manual and under feedback it says "zero."

I do remember on another "switchable" amp I referred to, the Mesa Baron, on the back panel there were knobs to adjust feedback. I do not recall playing around with that particular adjustment during the two days that I auditioned that amp.

As far as "tube roller’s dream", I should clarify that I dredged that up from my memory (which is USUALLY pretty good) but since I cannot find the blurb for whichever amp it was, I probably should not be providing a designer/manufacturer’s quotes that I cannot find to reference back to.

"Zero" feedback? Really? I’ve looked at the CAD-280SA V12 manual online and it doesn’t mention feedback, but perhaps that's a different model. Hard to imagine they use NO feedback.

@dogearedaudio , there should be a page labeled "SPECIFICATIONS" that interestingly is not numbered, but it looks like it would be page 5.  (I say looks like, because the pages are starting to come loose in that particular manual.)  Anyway, dimensions are listed. next weight is mentioned, next circuit type is mentioned, and then, under circuit type, it lists "FEED BACK:  Zero".

And I am not arguing with anything you say, as I truly have a limited understanding of most of this, but just telling you what the "CAD-280SA V12 OPERATING MANUAL"  that came with my amp says.

@dogearedaudio , coming back to the feedback, and again not arguing with you, but almost at the bottom of page 4, the page I believe should be just before the un-numbered specifications page, there is a header "OVERVIEW AND CLOSING THOUGHTS" and under that header Mr. Had had written that, "The V12 is in reality four single-ended amplifiers operating without any form of feedback."  

Apologies if this came up earlier in the discussion...Do you guys re-bias and adjust for volume difference when you change between UL and triode? UL plays notably louder at the same volume setting than triode on my amps, and I’m assuming others too.

@knotscott , the owner’s manual says nothing about needing to adjust the bias when switching from triode to UL or vice versa, and I have checked the bias after I made this last switch and there was no noticeable swing in the bias.

As far adjusting the volume when moving from triode to UL, I would have expected that myself, but it seems as if I am mostly leaving the knob on my SLP05 where it was. Maybe turning it just a hair down, but if so, only a hair or so. Not much at all. Mainly what I noticed was a change in "the body" of the sound. (or maybe the "shape of the sound" or maybe the "location of the sound."  I am bad with terminology.) The gain on that preamp when using the balance ins and outs (and that’s all I have used so far, but I am thinking about experimenting with that also) seems pretty high to me, and with most CDs or SACDs it is about 9 oclock give or take a hair.

@brianlucey , what sonic changes did you note when in 1/3 triode 2//3 UL and in vice versa?

@atmasphere , I am not arguing with what anyone is saying; I have stated before that I am illiterate on these subjects.  I was simply directly quoting from the owners manual that came with my amp when I bought it.  Although he didn't write it that way, is it possible that what i quoted was meant to only be applied to triode operation?  

I was commenting more in the fact that the manual was either poorly written or misleading.

@atmasphere , that could be; this subject is over my head so I will not offer an opinion..  As far as the UL design, Mr. Had does state at least a couple of times in that manual how much he likes triode.  He even refers to himself as "a triode crazed audiophile" in that manual and at one point goes on to say that this amp "sounds better" when operated in triode.