SET Shootout China VS The USA

Put another way, this isn’t about KT vs 2A3; IME its about design ~~~~~~~~~~~~~~~~~~~~

 

man I want one of THOSE amps the EL95 you describe. wow. Sounds just like my perfect cup of tea. I am about to upload a video after I post here. In the video, I make the claim the KT88 does not render the music such as I am hearing via the 2A3. Although both techs here threw tomatoes at Jadis Defy design,, neither can pin point exactly whats wrong,,excep there are ONLY 4 bias pots for TWELVE!!!! tubes, Jadis cheated on that mess up. This amp needs 12 bias pots accessible from top panel. Come on Mr Jadis,,just wwhat were you thinking,,,ohh yeah French asethetics, beauty,,GOT it, Give me 12 bias pots top panel please, I;’ll ship it back, you pay ship both ways to france.. Design?

 

Every KT amp I’ve heard, about 5 , EL34,88,120 all sounded about the same. To me it comes down to 88 vs 2A3. The sonics are in the tube, much less the design. Although I will say i prefer AU along with AX in front end as superior pre section , this way I can get Teles in the sound. Got to have Teles in pre. My tech’s UX50 has 12AU7 and some other taller pre tube,,which I am thinking is the reason i prefer this Yaqin over his UX25. Teles are simply magical. I’m not saying design has no influence, just saying it really boils down to power tube vs power tube.

I could not tell much dif twix a EL34, 88 and 120. Whereas DHT’s have a **signature** character. This is what i am trying to say.

Not saying all DHT’s sound same, just all have a  signature midrange  linear magic.

But I’d bet the KT170 Jadis sounds not much dif from their EL34 designs. Speaking of only midrange, not bass, not highs.

vs the liquid, magical mids of DHT’s.

Every cd I’ve tested sounds like new music vs the KT88’s **signature sound*. Again not that all KT88’s sound the same. I did not like the ever popular Gold lions, Svets were better,,hoping the EH’s beat out the Svets so I can decide either to keep the KT88 amp or sell it (= dump it) Can the reputation of Electro Harmonix 88 save this amplifer?? But why listen to a midfi amplifier when I can listen to hifi amplifier???? Makes no sense. KT88 mid vs 2A3 high.

chips + the Class A JFET opamps, loaded with tiny cjips. All make for highly sensitivite DAC setup to moisture. ~~~~~~~~~~~~~~~~~~~~~~~~~~~ This may have contributed to the pops while cd plays,, but then I played same jazz cds with ceiling LED with dimmer OFF, and pops completely disappeared. DAC did not like 100% humidity + cool temps + static energy in air/cold front energy + LED ceiling with dimmer. No pops and just was able to upload another video.

Hi @atmasphere ,

Why did you use EL95 in ultralinear mode? Why you didn't use 2a3 or 45 tubes for your push-pull amp?

Regards,

Alex.

The new OP Q is

KT series tubes PP

I've been exploring SETs for nearly 30 years. I started with 300bs, then it was the 2A3, finally the type 45. Then I decided to see how a PP 45-based amp would sound and it ran circles around the SET version- smoother, more delicate, greater resolution, more grunt, better bass- no downside whatsoever.

Of course I was measuring these things too. What I found was the distortion signature defines any amplifier. Its what we call the 'sonic signature' since distortion is very audible as tonality.

Since SETs express a certain type of distortion (quadratic nonlinearity) and a fully differential amp expresses a different type (cubic nonlinearity) and since PP amps with single-ended circuits express both, I set out to see if I could build a PP amp using small power pentodes that could outperform SETs of the same power.

This little amp makes 5 watts and is class A. It uses EL95s which are a little brother to the 6AQ5. The tube is meant to be very easy to drive. I set up the output section in ultralinear, using cathode bias so it would have a substantial differential effect on the output section, giving it greater linearity. I then built a 12AT7 differential amplifier to be both the input voltage amplifier and driver. So the amp is fully differential and thus has a cubic nonlinearity.

A cubic nonlinearity expresses the odd ordered harmonics since the even orders are cancelled. A quadratic nonlinearity expressed both even and odd.

The ear treats the 2nd and 3rd harmonics the same- they are relatively innocuous. But they are also useful as they serve to mask the presence of the higher orders. That is why an SET sounds so smooth, despite making more of the higher orders than any other kind of amplifier!

Because the 2nd is suppressed, this little amp makes a fraction of the distortion that an SET of the same power makes- its about 0.5% at full power and vastly lower at any other power level, and because the 3rd harmonic is able to mask the higher orders, its very smooth. Its actually smoother than any SET I've heard, while also being more detailed and transparent. It also has wider bandwidth, being full power to 100KHz and good down to 5Hz.

Having heard it, there is no going back to an SET. I wanted an amp small enough that it would be good in a desktop or bedroom system, also good for headphones or a main system if you have speakers of sufficient efficiency.

Put another way, this isn't about KT vs 2A3; IME its about design. You can make a bad sounding PP amp and you can make a good sounding SET. But you can also make great PP amps that go places no SET can at any price: smoother, more detailed, more musically involving, IF you know what you are doing with the design.

 

@jond 

 

Yes my tech speakers often of this **45** tube.

Looking at a  pic,  tube looks super.

have a  feeling its the one Im after, Yes very low watt as  mentioned in Triode's web site and mentioned *speaker choice is critical..** Mentioned something like 100 db sens speakers..

Mine are dual FR + dual T's. 

tweets 91db and FR 95 and 93.

with the ohm load, might have to stay with DHT PP circuit, for a  booost in power/dynamices

Actually listening to a single tube SET UX50, , now this PP2A3, I prefer a  PP DHT design.

I love the dyanmics of this dual tube circuit.

Not sure when the Defy will IF ever get tubes,,,,, man, the wrong roads we travel down....costly....never  taken much interest in DHT's due to alotttt of , half baked , misleading nfo I read here on audiogon decades ago concerning SET amplifaction. Another reason i never took a  interest in DHT's is  lack of exp with a  FR speaker.

All this is completely new to me.

Seems I am saving the very best amplifier for,,,last. 

Like a  good old rare Bordeux. 

The 45 tube is a fantastic tube to many DHT enthusiasts it's their favorite. However because of the exceedingly low power it's not for everyone and proper speaker matching is essential. I prefer it and the 2a3 both to the 300B tube as a general rule but obviously that's amp dependent there are tons of good 300B amps out there.

Correction

IDHT and pentode tubes are not synonymous. Pentode =5 element construction. IDHT is a triode =3 element construction.

Charles

and here ya go

WOW factor off the chart.

These designs are blast off rocket ships to a   magical musical universe.

Your music will never be the same. 

Will never have sounded this good.

You will RE discover your favorite music. 

As in,,**WOW I never knew this singer/ band had such talents..**

http://www.triodelab.com/45-triode

 

 

You are discovering the world of DHT tubes.

 

~~~~~~~~~~~~~~~~~~~~~~~

 

**another world**. Bigger.

 

Another universe. As you were typing this message,,

I was on the Inet searching these *DHT** tube designs. I’ve heard amazing things about the **45**, and other DHT tube circuits Just unreal. WOW factor off tjhe charts. Look its high time we get off discussing KT series tubes. Audiogon past 20 yrs has been ALL about KT series tube designs. I;’m sick and tired of of the old standard fare, like stale bread./

Yes a KT is a nice sounding tube. But it ain’t nothing special such as these DHT’s deliver. 2 **completely** (hyperbole necessary) different soundstages. You guys know how far I’ve gone in hypeing FR speakers as not only the best choice, but,,,well I refuse to finish the sentence... Again here with the **DHT** Universe discovery,, the sound fields lifts you off the earth into a new unknown (KT exp well known /explored) planteary system.

For months I was perplexed as to what amp design will open up the magic of a FR system..

I searched all and evey KT offer. Close to addinga 2nd KT series, like a EL34 low watt amp,,, By sheer luck (man do I need a break on luck in my choices lately)) I hit on this 2A3 PP rare gem. So as we close out the year, i am going to add to my prognostication (big word I know, but have a bit of that old spirit with me,, a bit I said, not to the degree of the old masters). FR as speaker choice, 1st system, wearing crown jewel And these DHT SET/PP as the preminent place among audiophiles choice in amplification power. Its comming, I can see it, but its still some years off. Sterophile, 6 Moons still pumps out massive does of propaganda fopr the big KT power tube designs and the speakers that go with these sheer power blocks, the low sens/low efficient blood(fidelity) sucking xover type speakers. Neither of which is going away anytime soon as 1st picks.

 

~~~But a time is comming~~~

KT amps will be offered at *dime a dozen* prices on used retail sites. Rock bottom. Whereas you’ll be lucky to find a good deal ona used SET/DHT type amp. = Minisclue discount. maybe 10% off list. vs PP amps, now nearly 30%++ off list. jadis DPL Linestage, with takman, Mundorf and Teles, Jadis Defy, Takman, Mundorfs, Teles,,, I gave jadis all the best,,But its no match fora DHT PP 2A3 design.

The future is

~~~FR + DHT~~~

 

@mozartfan

What you’re referring to as "SET tubes" are technically DHT(Directly heated triode) true 3 element tubes (45, 2A3, 300b, PX 25,211,845, 805,50 and so on). Your reference to "KT type tubes"  are IDHT (Indirectly heated ) with most of these tubes being pentode, 5 element constructed tubes. You are discovering the world of DHT tubes. Welcome😊, there’s a ton of information available via search that can go into as much detail as you care to explore and learn.

Charles

Someone text me say his UX250 SET has no issues driving his vinatge Realistic Nova 7’s and Grafyx SP10’s, both double stacked,, thats SIX WATTS...so just **what** do I know...

ahhh you know what, Here is where his Colbalt out trans kick in with a bit of slam power,,, vs the Yaqin’s Z11 weaker trans. So it is possible he is having some **success* driving LOW EFFICIENT xover types with a SET, Cobalt trans.

 

Few of us have cobalt trans in our low powered amps.

So that caveat aside.

basically this topic OP has been altered.

Its not about a chinese designed amp vs a USA amp design.

The new OP Q is

KT series tubes PP

vs

Low SET type tubes PP (300B,2A3)

 

For all low sensivity speakers/xover types, KT series , EL34,88,120,150 are the ideal tube for giving dynamics to a highly INefficient speaker.

These speakers demand power, Which the KT has to offer.

 

In high end HIGHLY efficient speakers such as FR. lower powereed tubes such as the 2A3 is the superior choice. Lets say **marriage made in heaven*.

So I will not commit to say the lowered powered tubes, are superior in soundstage/musical sound field..only that witha FR the best and ideal choice is NOT the KT series.

I’m closing out this year with 2 major discoveries in my experiemental journey ~~~search for high fidelity.

 Discovery  of FR as my dream speakers, DUALs at that.

and this Yaquin 2A3 which i had no idea what it was all about,, how it would perform.

It was intended as a low watt SET for light chamber/solo piano. Sort of backup amp.

Now the Defy has taken a distant 2nd place.

Yaqin wears the crown jewels.

2A3 does things a  KT series tube can't do.

 

Why are you supporting China's economy? ~~~~~~~~~~~~~~~~~~~~~~~ Look I am completely with you on this one. Chinese intellectual theft is real and affects us all here in the USA, in one way o more. I don't like what the chinese do, robbing our technology and then branding it and we buy it. Its theft. But in this case, I can't afford the other high end manufacturers ofg FR speakers nor the higher end amplifiers made in the EU and USA. Also are there any USA manufacturers designing a 2A3 PP amplifier at the moment? At a price I can afford. In this case, hats off to china for bringing me wonderful components which fulfill my long quest for a beautiful musical soundstage.

Dac chips until this thread. So thank you for that if nothing else. ~~~~~~~~~~~~~~~~~~~~

 

. I’ve had the DAC now 9 months.

Yesterday was a very wet 100% humidity and cool. I’ve noticed during a rain , next day, DAC needed **drying out time**, Yesterday was the worst...So what i am doing to help prevent this longgg dry out time,, is 1) placea paper bag over top of unit where there are vent holes placed along top, 2) turn DAC on early in the AM< WITH bag left in place, this way heat builds up and drys out any excess moisture. Beats using a blow dryer, which did not help all that much... , Also I could put back in the window my 5k btu window AC and run it at night, like a dehumidifier. If I have to I will. I note the pops are more frequent while in play, with all my jazz /pop cs which have some marks on the surface,, my classical cds are near mint have less pops. So the entire Shamling drive + DAC together are being sensitive to excess moisture + cds in avg condition. This issue only happens on certain super high moisture days. 100% humidity + rain + cool front which makes air highly energized wind = static energy. This Jadis DAC is loaded with chips + the Class A JFET opamps, loaded with tiny cjips. All make for highly sensitivite DAC setup to moisture.

Ok I read the who thread.

Wow!

Merry Christmas

One thing I've learned in audio is there's always something better ~~~~~~~~~~~~~~~~~~~~~~~~~~~ WEll sure I mean if we bring Kronzilla and Wavac into the discussion, Jadis has to take a distant 2nd place. There are other UK designers also employing the 833 and other super massive exotic SET type tubes. But in its price category, Jadis reigns pretty high up there in craftmanship. This is my point, Jadis eraned and well deserves its reputation. Is my point. I did go a bit hyperbole when i said **THE most** when in fact truth is, **among the most mucical in that price group..*

Why are you supporting China's economy? I don't get it. I can understand an iPhone only.

I don't know anyone who thinks Jadis is the worlds greatest amplifier though I'm sure there are some. One thing I've learned in audio is there's always something better sounding you just haven't heard it yet. It leaves you with a certain amount of gratitude for the sound you have and humble for knowing it can be bettered. Well most of us at least.

Oh My! You’ve had a Chinese made, sub $1,000 push-pull 2a3 amplifier for less than 72 hours and you just proclaimed it what? Better than anything the US or EU can muster? You just don’t know what you are talking about. There is absolutely nothing wrong with not knowing what you are talking about, there absolutely is something wrong with your proclamations. The wet chip syndrome has nasty side effects.

 

 

Thank you Charles! And @mozartfan I have to say I've never heard about overly moist Dac chips until this thread. So thank you for that if nothing else.

Curious as to why Mr Jadis did not come up with a  300B PP and also a  2A3 PP design???
*IFFF* thats  a big IF, FR  interest ever does get steam going in its train engine,,, you might also see interest begin flowing into lower power PP designs like the 300B and 2A3.

But as we know

1) general interest in all things audiophile are not as strong as they were 10, 20 years ago.

The new commers have all this digital  gadgets and head phones.

2) you can find so many offerings on the used market, which cuts into new sales, thus new designs can't get the funding. 

 

3) xover speakers just seem to  facinate and dazzle both old and  young audiophiles.

Guess this has to do with the typical american ego trippin on power. 

 

I'm doing all I can to push the lower power amp agenda ,  as the superior musical soundstage when paired with the right speaker.

Hopefully Mr Jadis is reading my post and  will at least ponder is the company should slow down on  big power amp offerings. And start designing amplifiers that offer finesse and fidelity, such as the 2A3 PP design.

I think china's manufacturers  have the leading edge over EU and USA companies and this trend will continue.

And you know it. 

My amp, and speakers ,  Made In China.

can you believe it. China beat out the worlds best amplifier, Jadis. (Both techs here  , just loved to trash the Defy all the time...) 

A tube made all the difference. 

 

While you are at it, why don’t you make a video playing Keith Don’t Go or Peel Me a Grape?

 

Jokes aside, narrating a slow motion train wreck is nerve wracking to witness.

Had hoped to upload YET another video.

Miles Davis Kind of Blue.

DAC has mositure issues, we live 10 ft below sealevel. When the conditions are **right** cool./cold, moisture pouring in from the Gulf, DAC gets cranky, the chips are damp.

I now have a paper bad over the vent holes at top, this will keep heat in the unit and keep chips nice N dry.

So no upload tonight.

Let me say, the 88s did not present Miles Davis like this Yaqin.

 

For me the KT series does not even exist.

So this year, I’ve dumped 2 component models,, xover/low sens speakers and KT series tubes. (yes will retube the Defy with EHKT88's, museum  piece)

heee hawwww

Not interested any longer in the 845 design.

@jond 

Lovely! Thanks for sharing. No doubt the Deja Vu proprietors know their customers tastes/desires very well. I bet this amplifier sounds fantastic!

Charles 

@charles1dad Lets just say when I took my EL34 amp in for repairs the guys at Deja Vu knew just what they were doing loaning me this amp. 😉 Here is a gratuitous pic of it 😎

 

 

 

@jond 

You had that el 34 for quite a while so I know how much  listening enjoyment it must've brought you.  Your current 2A3 push pull amplifier has to be quite special to have  drawn  you away.😊

Charles 

It's about the tubes ~~~~~~~~~~~~~~~ When you say about the tubes,,,d o you mean rolling might add a nuance or...take away from the sound?? My tech here Richard, mentioned the Mesh plates I;m interested in, might not make, in fact **most likely will not..* make much gains. Have you tried other 2A3's.? He has a perfect set of NOS RCA's, But i'm opting for the FUll Music Mesh as my next tube. I;ve seen some very pricey Carbon plates, Titanium plates many others. Pricey, so I want to make my 1st roll of the dice, count. IF the resistors are in fact carbon, right off swapping to Takman Rey metal will make a nice gain. Carbon are great for jazz fans that love their music real smoothhhh. carbons do just that. Clip off the peaks in fq's. Flatens out the sound. Its intreguing,,for about a few days....

sound comes out. But if you want to hear proper imaging out of them, your head needs to be in a vise so as to be held always in the right position... The box in the image above this post looks as if its ported. Did you do anything to prevent slap echos inside the box? ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Thats correct, Just get any old speaker box, say 50 liter give a take 10 liters,,,slap a pice of ply over the front with a W8 + W6 hole cut,,and your-good-to-go. a bit of attaic insulation, actually i need to add some more along the walls, Cut ya a port, any size you wish. Shes goodtogo. The head in one exact spot deal you are refering to pertains to the Tang band 2145 and the smaller brothers in this same design. Its beams. Bass is near identical to the DL wood cone, ,,well I should say close,,,mids are close,l highs are a bit better in the TB2145. But it has a baeming issue,,which I could never accept. These DL's have zero beaming. Nada These DL's are basically the Legendary Coral Beta 8's reborn. Like the old Phoenix in the Fire resurrection. The DIYers will never accept my dual things. While others might hate my speakers, I love them. Truly a Frankenstein. \ Carlson(the famous YT tech master) in his lab, might test and find they are loaded with breakups, distortions, colorations, all fatigue-ing, no fidelity.

@mozartfan Hey it's great you like your system so much at the end of the day that's really all that matters. Don't think folks here are arguing or disagreeing merely sharing our experiences with many different amps. My previous amp was a pushpull el34 amp triode wired and Class A with vintage output transformers it sounded fantastic. My current pp 2a3 amp also sounds fantastic but different it's also triode wired and class A different vintage output transformers. It's about the tubes and everything else in the circuit not to mention the circuit itself. Happy listening!

KT type tube offers wonderful colors, imagery, low distortion, no coloration, no fatigue.

I know this fora fact hearing the DEfy7.

Jadis Is not the only one to make amps based on the KT88. You might want to hear a Harmon Kardon Citation 2 prior to saying you know how a KT88 sounds. Keep in mind this comes from a manufacturer that has only made triode power amps (and now also a class D amp...).

Regarding your speakers, what you are experiencing is that there is some destructive cancellation that is happening in your system because of the spacing of the drivers. This is actually helping prevent some of the more painful comb filtering that can otherwise occur when two such drivers are placed side by side. I’ve heard speakers set up this way. They are not bad, but seriously are not the last word in resolution by any means. They are attractive IME because all you have to do is get them in a box, wire them up and sound comes out. But if you want to hear proper imaging out of them, your head needs to be in a vise so as to be held always in the right position...

The box in the image above this post looks as if its ported. Did you do anything to prevent slap echos inside the box?

Now I agree dual FR makes no sense whatsoever, Its a  completely ridiculous idea,,a  single is really all you need. Duals can make confusion in the sound waves,, 2 VC's bouncing off each other all muddy, convoluted, distorted, just a  blob of ,,poop..

But for some reason I like the sound of this poop system. 

..

The opinion in this video reflects my own subjective reaction to the 2A3.

KT type tube  offers wonderful colors, imagery, low distortion, no coloration, no fatigue.

I know this fora  fact hearing the DEfy7.

But if It came down to chosing one or the other,,I'd have to chose the 2A3 as my premier system. 

Bass are near equal, highs a tad superior in the 2A3, buts its in the midrange where the 2A3 opens up recordings that a  KT series tube just does not make happen.

 

2A3 beats out the KT series tube, EL34,88,120, 150

If you feel offrended by any of the comments in my video, just disregard and move on.

Its only my opinion and 2$'s ,,,which ...will get you a  only just a   Starbucks $2 cofee.

 

And no I ain't budging on my opinion.

 

 

 

@mozartfan It would be really cool if you could attend an audio show or maybe there is a great dealer near you. You really owe it to yourself to hear the differences between all of the topographies so that you can find out where you really are.

 

I remember vividly many, many moons ago when a very helpful dealer played a series of amplifiers for me, several tube and several solid state, in descending order of price. He played them through a very popular speaker at the time. My conclusion then: I couldn't hear much (if any) difference. He agreed. That made me feel great.

 

Then, he repeated the same exercise with a pair of exceptional speakers...everything else the same. Same descending order of price, etc, etc. The sonic differences between the amps was striking, astonishing actually. The dealer knew what he was doing. He was a WWII era radio operator, had started a radio repair shop post WWII and evolved it into a fine hifi shop which made it into a third generation. His moral to the story was to pick the speaker you like and then if you can't tell the differences between the amplifiers, relax and buy the least expensive amplifier whose sound met your goals.  His BIG advice though was just because you can't hear the difference doesn't mean there isn't a difference, it just means your speakers aren't up to the task.  He added that if I ever intended to upgrade the speakers then always buy the best electronics that you can afford at the time to ensure the speaker upgrade down the road would have the chance to pay dividends.

 

No offense intended @mozartfan but if you can't hear the differences of all of the vast array of amplification varietals that you have implied you have experienced first hand, then it isn't the amplifiers, its more than likely your speakers aren't up to the task of revealing the differences. You should be celebrating though! If you like your speakers and all of the amps sound similar to your ears and you are happy with the sound then pat yourself on the back!!! You found happiness and can achieve it for an exceptional value. @atmasphere is an amazing resource, he is an absolute expert when he is talking about amplifier design (not just OTL's but generally all topologies). He would be the first to tell you if you are happy with the sound, then stop. He would also tell you that amplifiers sound different and if you don't hear the differences then its probably the transducers.  

 

I recognize, however, that you may be more likely than not going to argue with me and say that it can't possibly be your speakers...in that case, enjoy the solo wrestling match. Warm regards and happy holidays.

I also think, using two fullrange drivers in parallel and tweeter (without properly designed filter) works against basic idea of fullrange (a point source of sound.) It makes sound congested and messy and destroys soundstage and focus ~~~~~~~~~~~~~~~~~~~~ This is exactly the same argument raised by ~~THe Association of Full Range Speakers** aka THE Club of FR Enthusiasts,,over atn the DIY forum, Full range section,.,, **We tried this dual thingy,, did not work, wont work,,dont even consider attempting such a scheme..** WEll I broke THEIR rules and disobeyed THEIR authority,,,**I did it my wayyy** as old Frankie Sings They asked to see measurements, graphs, testing lab results etc. I had none. gave me the boot PERMANTLY banned. hahahaha Did not learn EVEN one thing from those **scientists** haha I like to break the rules, or lets say go against common opinions/beliefs. As I posted elsewhere,,this Dual thing will only work under with certain drivers. You nor anyone else in the world might say **and you actually like THAT sound???** Yep , dont touch my Dual system, I love it. 2nd tweeter arriving next wek, Dual FR + Dual T's. If all the big guns can get away with multiple driver systems,, I figure why not I.

Each of these changes can make a dramatic influence on sound! ~~~~~~~~~~

 

I  know some audiophiles are not won over on swaping parts. = A cap is a cap is a cap...

I am a believer.

I prefer Takman Rey metal vs any and all carbon **smoothhhh* resistors. Caps, Mundorf SESGO or Silvergold EVO, whatever I can afford.

Tubes also make a gain, Teles in the pre, and have yet to roll these stock Psvane. My tech thinks there is not much to gain swaping out power tubes...we will see, that experiement waits til mid summer.

really hesitant to make a blanket statement such as yours in the quote above- in a nutshell, its blatantly false. ~~~~~~~~~~~~~~~~~~~~~~ OK grant it, I have not heard a KT type linear SET, nor a EL34 Triode. Perhaps they offer same , even superior sonics vs this 2A3. Quite possible true, But as you say, there are so few Ultra Linera KT88 and Triode EL34 avaliable. I had the Cayin EL34 Triode/Ultra, but sold it off, bessides the trans were a bit too small for my preferences. I am speaking of a PP KT series amplifier, such as the Jadis Defy7 one of the finest sounding PP amplifiers ever made. Can not match what i am hearing in the 2A3. In some passages, both very close, in other cds, the 2A3 is more evoloving, **REVEALING***

Hi @mozartfan ,

You can’t compare amplifiers and make conclusions just by output tube type and transformer! There are so many factors like schematics and quality and quantity (capacitor value) of parts.

I have DIY 300B SET for many years.

During 15 years I made dozens of modifications to this amplifier.
1. I tried different types of 300Bs, 6F6s (driver), 6sn7s (input) .
2. I tested 5 different kinds of coupling capacitors.
3. I upgraded the power supply including choke, capacitor types, value, schematics.
4. I changed the bias current of all tubes.
5. I changed cathode resistors and capacitors.
6. I changed output transformers.
Each of these changes can make a dramatic influence on sound!
If you don’t try, you don’t have any idea how all these things are important.
For example, in my case, upgrading of cathode resistors and capacitors made more difference vs upgrading output transformers (from James Audio to Hashimoto)!
Bias current of the driver and input tubes made a huge difference!
Coupling capacitor quality is supercritical too!

I also think, using two fullrange drivers in parallel and tweeter (without properly designed filter) works against basic idea of fullrange (a point source of sound.) It makes sound congested and messy and destroys soundstage and focus.

Regards,

Alex

**the 2A3 PP  is just 1 of many options, 1 circuit is not superior to any other..**

BALONEY. Just a simple one  size fits all platitude.

The 2A3 PP is superior to any and all KT circuits.

@mozartfan 

If you run a KT88 UltraLinear, using an output transformer with the UL taps set up properly, you can get the same or better linearity out of that circuit that you get from a 2A3. If the taps aren't right neither will be the linearity so I am stressing that point. If the driver and voltage amplifier are then fully differential, the distortion without feedback will be dramatically lower than the 2A3 amp at nearly any power level.

You'll wind up with a more transparent, more musical distortion signature and therefore a more transparent, more musical amp with a lot more power.

Although I don't know of such an amp there may well be one out there (most I know of use textbook circuits from the 1950s); having been a manufacturer for over 47 years I'm really hesitant to make a blanket statement such as yours in the quote above- in a nutshell, its blatantly false.

 

@MF... What's "dispication"? Can't seem to find that one in my audiophile thesaurus 😵

@ Atmasphere

 

Yes my tech Richard, just wrote  to say 5% as vol gain goes up more distortion,, that 5% goes down as vol gain goes down.

I listen at ridiculously low SPL levels, so for me this 5% is no big deal.

well yes at full blast evena KT88 will show distortion.

My tech and Charles among others wish  that I retarct some of my strong opinions, as if to say 

**the 2A3 PP  is just 1 of many options, 1 circuit is not superior to any other..**

BALONEY. Just a simple one  size fits all platitude.

The 2A3 PP is superior to any and all KT circuits.

I would bet outshoots Jadis' new super KT170  Crown Jewel.

 

Yes I understand as a  FR sens goes up, better response froma  low powered SET or low powered PP *SET type tube* 300B/2A3.

But as you know the higher in sens you go up ina  FR, lower the bass response, = too forward a  midrange.

 

95db sens ina FR is my very limit.

I would not buy a  96db sesn driver, as there is no way I can intergrate a  W6 FR.

Just 1 db makes all the difference. I got very lucky on the davidLouis

VX8 95db

VX6 93db sens

made it by 1 db on both

If the VX6 was 94db, it  might cause trouble.

Finally everything is falling into place. 

Hundreds of hours research.

Lots of  cash, mistakes, errors.

Luck has finally tured in my favor.

About to upload yet another Yaqin vid/

Might stir up the honets nest, so let me put my protective gear on....

 

 

@mozartfan Just so you know, that 5% figure is for the tube alone; it does not include the rest of the circuit of an SET. The distortion of that at full power is more like 10%. If you really want to hear what almost any SET does, you need a speaker that makes no demands of the amp over about 20% of full power, so as to avoid higher ordered harmonic generation. Of that means a speaker that is more efficient than any 'full range' speaker can be- for a 2A3 no if ands or buts you need horns.

At least if you want to produce realistic sound pressure.

@larryi Funny you mention hyper realistic with the 2a3. When I was running 2a3 monoblocks with Omegas I often thought about this particular characteristic of internal luminescence. Mids had the sense of being lit up from within, very unusual, never heard this prior or since. ~~~~~~~~~~~~~~~~~~~~~

 

WOW now thats a amplifier. 2A3 monos. Unreal.

 

Agree, the KT series ain’t no slouch , as i’m listening to sym via the 2A3, the KT88’s deliver a similiar result.

We are only talking slight shades of nuances here. But over all, for my preference in soundstage, I prefer the 2A3 PP with a FR speaker. Low watt amp always works superior with FR vs a KT PP. Its my personal preference , maybe not yours. But as you guys know ,

I’m done with xover low sens speakers.

And I know darn well none of you are about to follow my lead.

FR are superior. For so so many reasons. call me Philistine all you want.

I am The Iconoclast.

 

and yes I did correct Yaqin  sp in the YT uploads. 

@larryi  Funny you mention hyper realistic with the 2a3. When I was running 2a3 monoblocks with Omegas I often thought about this particular characteristic of internal luminescence. Mids had the sense of being lit up from within, very unusual, never heard this prior or since.

 

@mozartfan  While its good to be excited, your credibility is seriously lacking. I mentioned it prior, all topologies, systems, equipment may move someone. This is all subjective evaluation, you come across as being objective when using extreme adjectives such as best, greatest, only, etc.

 

Saying particular tubes always sound a particular way is simply not true. As others have mentioned previously, so many variables to account for.

 

Your 2a3 tubes in your particular amp in your particular system really say nothing to us.

@mozartfan 

 

I prefer Faith Hill, Diana Krall via the 5% distort 2A3PP vs a KT88PP. All day long. My suggestion is if you are going into a FR system as a 2nd system, this is the amp to buy..

 

Sadly you lost half of your audience with your first sentence and the remainder with your last sentence. 

@mozartfan sometimes the crowd is actually right ~~~~~~~~~~~~~~~~~~~~~~~~~~ My mantra is Never ever follow the crowd. If I go the wrong road, I tack it up to exp. Otherwise I follow my own course after my Thor upgrade disaster and listening to my tech saysing **Yes seems 1 of the 15 year old Millenniums are 1/2 ohm off from the other,,,better spend $700 on a new pair..** so I did,

For absoluetly nothing.

Both pairs sound identical. Tweeters last FOREVER if not abused, only swap out diaphram every 30+++ years, Thats it, $50 bucks. Remember what old Frankie sings **And I did it my OWN wayyyyy** I never ever follow the crowd.

to make judgements hastily. But in the end you have to be you. BTW, DHT push pull amplifiers are nothing new, have been around for some time ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

I bought the amp, behind my tech’s back, had he foreknown I’d buy the amp, he would have pulled out his 1929 RCA tube data book and pointed out 1st data ~~~5% distortion on self bias** wopping,,

and I may have dismissed his 5% as no big deal.

I would have thought,,well thats 90 yrs ago, perhaps Psvane has developed a new tube that avoids most of this 5% distort,,,, He again pointed it out as he biased the tubes. Auto bias 2.5 %. much better, but this yaquin is self bias 5%. and pointed out other issues in data witha AB1 PP 2A3 design in the tubes plate dispication, voltage and such. But he did go on to say **who knows you might like it in spite of these inherent issues..**

And now I know about 5% distortion,, its there in the ~~luckily ~~~ upper mids, not   upper bass/low mids,, which would grate on my nerves...

,, Its only in certain fq’s, not the entire range. My DL’s can deal with it, as both speakers are near distortion free. They can absor the 5% with ease. The Philips tweeter kicks in at 5khz, so it does not have to deal with the midrange distortion. The only way this fantastic amp will work ina system is IF 1) FR speakers ONLY 2) FR with very low distortion peaks , that is neutral throughout this 5% distortion from the tube. Trade offs as usual. I accept the 5%, but in return the tube rewards with very nice midrange, vocals, soundstage.

The KT88 has , not sure like 2% distortion,, but you do not get the superior ```hard to say exactly~~~ but superior something or other.

Now will the Full Music  Mesh Plates

soften up some of this distortion, mellow out the ever so slight harshness... remains to be heard. Stay tuned.

I prefer Faith Hill, Diana Krall via the 5% distort 2A3PP vs a KT88PP. All day long. My suggestion is if you are going into a FR system as a 2nd system, this is the amp to buy.. @ Charles No very few of these 2A3 PP amps in the market place, Plenty of SET 2A3, this Yaquin and maybe 1 or 2 others in the PP design. This amplifier will not work with xover low sens speakers.

 

Dont even try.

@mozartfan sometimes the crowd is actually right. In this case you received the amp sometime on 12/18. Later that day and into the 19th you are proclaiming the amp a world beater, which may or may not true…its your world and therefore your world to beat. Respectfully, you don’t yet understand what the tubes or the amp will sound like. You ponder a Jadis kt170 based amp when few have heard that amp let alone the new kt170 tube.

 

To the Audiogon community’s great credit, people are being very gentle with you but the homebrew, fr driver speakers with an extra driver and a tweeter daisy chained as your baseline with an unknown Yaquin amp and tubes with abiut 10-20 hours on it at the time of your proclamations….seriously, you should give yourself a chance to hear whats going on and there is literally no way for you to get a taste of what you may or may not have in this exercise. Give it some time, make notes of what is going on, how it is changing and whether its for better or worse. 

The meshplate triode tube I am familiar with is the EML 2a3.  I ran a quad of these in my Audio Note Kageki amps (parallel single-ended).  I like their sound.  The soundstage was gigantic, open and enveloping.  If someone thought it was a by hyper-realistic (in a technicolor sort of way), I would not disagree.  A friend thought it sounded a touch phasey; I would sort of agree, but, image placement was precise, so it was not truly out-of-phase sounding.  

The most exotic meshplate I've heard is a meshplate 252.  This tube is so rare that I know someone who was offered a trade of a pair of solidplate 252 plus $20,000 forin exchange for a pair of meshplate 252s.  The offer was declined. 

By the way, the Western Electric 59As (the amp that runs 252s) is a terrific sounding amp.  I could never afford the amp, and even if I had one, I could not see running it very often because of the crazy cost of its tubes.

if I follow the crowd,, what will I learn

@mozartfan 

Follow the crowd? I am the one encouraging you to continue your current discoveries in regard to tubes and particularly DHT tubes. Again you have a tendency (In my opinion) to make judgements hastily. But in the end you have to be you. BTW,  DHT push pull amplifiers are nothing new, have been around for some time. I do understand that this genre is new to you.  Best of luck to you.

Charles 

@ charles 1 

if I follow the crowd,, what will I learn?

Thats not already common knowledge??

Who would have ever suggested a  SET type PP design??

Never heard sucha  thing as a  low watt PP circuit.

Now my FR hasa   good match.

I was  always thinking,, KT PP is too much power. Yet SET's not enough dynamics for big full orchestra...

Dilemma.

 

However I did have at one time a  Cayin El34  smallest Cayin model , had ultra linear and triode switch..

I sold it off a  few months later,  thinking not enough drive for the Thors.

Yet perhaps a perfect match fora  FR system..

This  lil 2A3 PP is the answer to my quest for the ideal amplification for a  FR system. 

Hopefully the tubes can  hold up under a  four driver  load speaker system. 

If the tubes begin shorting out too early,, I may have to drop  some drivers and make ita  single FR + a  single tweeter.

Time will tell....

If so, then the Defy will have to carry the dual FR + dual tweeters/big orchestra. 

The 2A3 only for light chamber, solo piano., single FR + single tweeter. 

 

 

Oy vey!

Charles 

credibility. For instance, I have an el34 based amplifier in my closet which would likely change your opinion about absolute tube type superiority.

 

 

EL34=KT88=KT120=KT150 hardly even a nuance difference. One has more power vs the other is all I noted. now 2A3 is different vs KT series. Just my 2 cent opinion, Take it or leave it.

Last of my ideas on this matter,,,,, Jadis’ KT170, now here might be something special. Still I ’ll take a 2A3 PP (not SET) vs jadis KT170. Just my opinion, take ir or leave it.