SET Shootout China VS The USA

**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.

 

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

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***

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.

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.