SET Shootout China VS The USA

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

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.

I listened to ESL57 speakers in 3 different homes and liked these speakers a lot!

@atmasphere . One of my friends built a number of SE and low power push pull amplifiers on EL84 and 6V6 tubes. He mostly used similar quality parts for both SE and PP. But he preferred the results he got with SE by a big margin. He used classic schematics. He runs his amplifiers without feedback and with feedback. The question is why you and my friend got so different results? What is the difference of your schematics to classical EL84 PP schematics?

Do you use balance input "+" for input and input "-" for feedback? Did you publish your schematic?

Regards,

Alex.

Hi @mozartfan ,

Japanese SET audiophiles adore US made speakers like Altec and WE and German Klangfilm speakers. Jean Hiraga used Altec A7, A5 with crossovers designed by himself.
Another Japanese legend - Sakuma used 300B amplifiers and British made Lowther FR speakers. They don’t use Diatone full range speakers! They also preferred German EMT and British Garrard turntables over Japanese turntables.

EV drivers are much cheaper bult vs vintage Altec, JBL, Vitavox drivers.

I prefer horn compression driver speakers over full range for more balanced sound. BUT a few people use FR properly - with front horn and additional low frequency section.