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

Showing 1 response by atmasphere

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.