Push Pull KT vs DHT SET vs DHT PP


Time for another shootout.

As you know by now, my recent discovery of DHT's was a  mind blower,'Thinking I was orderinga  **SET* 2A3, when IN FACT it trurned out to be something more than a  SET, it wasa   DHT in a  PP design, Even bett-er.

So as I hear the 3 amps, I'm more convinced   the 2 best designs are 

DHT/PP such as 2A3/300B (have not heard), 45, 50 in PP.

Then we have the big power tubes in the SETs, 

211, 805, 645 and many others.

As I hear things, the DHT

's in all their incredible wonderful, magical,. mystical, magnificient,  varieties, seem to my ears to offer the finest high fidelity.

vs your KT series designs. (leaving aside EL34 in triode/SET)

Big bonus with the DHT's is the new sper high tech tubes now avaliable.

vs the KT which are same old, same old.

Besides with the new high sens Full range speakers big power PP are not necessary, not needed any longer.

IMHO higher sens speakers + lower power DHT's offers the audiophile best chance at higher fidelity. , Nuances and such. 

And if you really need bigger power for lower sens speakers,, there's always the higher powered 845 mono blocks.

DHT's to my ears offers more nunaces vs the KT series tubes.

They seem to offer a  more dark background, that is a  dead stillness which the music is then voiced across the black canvess of stillness. 

 

Such has been my impressions of two DHT designs. 

How has been your exp in DHT's vs PP.

I think when someone has heard a good DHT amp,  its more often never going back to a  PP amp. There are a  few who have heard/owned DHT's such as 300B, saying they tried it, was wonder-ful up to a  point,, then back to PP for the high dynamics.

Which is why my vote goes to DHT in PP design as 1st choice, then if you need dynamics, there is always the bigger SET tubes such as 211, 805, 845.

+ with the new high end/high priced SET power tubes, here you have the added bonus of upgrading the sound to a  whole nother universe of fidelity. 

vs KT88's,w hich mostly all sound  very close (though I did find the Glod Lions a  bit dull, which may have been corrected by the manufactuer in the past 18 months)  There's no such thing as a  super 88, But there are super 845's, 211's, etc. 

Not cheap, but well worth the extra as a  big nuance gain in the fidelity + new higher tech DHT's offer a  much longer tube life vs your avg KT series of 3k hrs. 

And if you have a  12 tube KT such as my Defy (soon up for sale) 12 X's $50 is not cheap to retube.

vs a  high end DHT which is simple to install, no tech required, ,  simple bias procedure, just plug the  new tube in,  and go another 5k hours or more. 

I did get 4k hrs+ out the Svet KT88's btw. But at a  risk.

When we add all things up,. pros and cons  in each column, the DHT's in all their varities come out the clear, clean winner.

How do you see/hear it?

 

Caveat : smaller KT amps with onlya  quad , is  more economic to retube vs a  high end priced DHT 845 which lists at $900 a  pair,

But I think you'll see the high end 845 tube   boasting high tech metals,  last 2 xs' the life of a   KT88.

So again, 1 to 1.

DHT's any way to  tally  the points,  gets the Gold. 

 

 

mozartfan

Yes Jadis is jadis is musical magic.

Thing is Jadis needs the proper tubes and caps,  to bring out all the nunaces locked up in this perfectly designed amplifier.

IMHO these Jadis  amp designers really know how to build a  circuit that will be  strong, resilent and near repair free for decades.

I've had no issues with this amp, now going on its 22 rd year.

 

In mid summer after my FR speaker project is completed, I will give the Defy what it deserves , requires to open up the voice at its best, EH KT90's. 

Everyone goes KT88, so i just followed the common vote, 

Which   on my particular path, has more often than not, taken me down the wrong road.

Now I tend to think things through very carefully as I am listening to music.

Like John Lee Hooker signs

**sittin here a  thinkin...**

 

One must weigh all the options and try to figure out the best plan of action. Reaserchresearchresearch,, hopefully the  best guess  will mean  less errors and more success.

 

And sometimes folks best advice is not what you were looking for.....

 

 

Good idea to keep the Defy 7! It will be good to use when you want to listen to music louder and more dynamic - Mahler, Tchaikovsky, Stravinsky ...

FWIW we built a few prototype amps using the 2A3 in push-pull. You get about 16 watts in class A. There are a lot of nuances that affect how tube amps sound.

If the amp combines single-ended and push-pull, like most textbook circuit so the 1950s, you get a bit of enhancement of the 5th harmonic which I think is why so many SET people say bad things about Push-Pull.

To really take advantage of Push-Pull, IME the entire circuit needs to be fully differential from input to output.  Put another way, you either run things all single-ended or all differential but not both for best results.

of all the quacky things I've said on audiogon over the past 2 decades,,this one here will surely top em all for looniness,,but here goes,,,as i am listening to the 2A3 PP,,,,it occurs to me, 

take Papa Useugi very very best design amplifier along with Wavac's 833 and Kronzilla's monos with 4 tubes per chassis,,and all 3 vs the Defy kt90,,, we are only taking 

~~~~Miniscule nuances~~~.

It all comes down to speakers.

I'm not saying  these 4 amps all sound identical, just nunaces off from each other.

factors such as cd recording quality, sounce quality, speaker voicing.

These + capacitor resistor quality, all come into the equation.

Amps are only one part of the equation.

 

I;'ve decided to keep the Defy and add in KT90's later this year.

2 amps is quite enough for the moment.

 

But any way,, thinkinga  new amp will make alllll that much difference is a  fantasy. 

Each  tube amp will offer a  nuance the others will not, Each will voice ever so slightly different from each other.

The word is synergy, all components add nuances.

This is how I hear the 2A3 vs a  KT tube. 

Different but can't say better.

Kinkless Tetrode". ~~~~~~~~~~~~~~~~~~~~~~ Yes am aware Look a Jadis Defy7 w KT90's will sound only nunace different from a 845. a tube = a tube, KT = DHT almost 95%, Its that 5% variation in sonics that I prefer DHT over KT's. Its time for me to go DHT's. Now if I had lived with a DHT SET amp for past say 20 yrs,, yeah, now I am ready for KT90' fidelity for more dynamics. Seems to me the bigger DHT tubes will supply this dynamic nuances that match the KT aural experiences. Time for me to move on,,,hard time right now selling my Defy w/o tubes. Might have to buya set of EH's and up the price, stereo eqip is slowwww sales right now. Things are just sitting on the used market.

The OP should acquire issues of Glass Audio, Sound Practices and Vacuum Tube Valley to enlarge his knowledge of tube audio.