JFET-only Circlotrons without negative feedback

Sure. However, the even harmonics should cancel out due the symmetry of the circuit. Why is this not the case here?

The complete identity of the shoulders is not only unrealistic. But it is not necessary.
It is more important that the non-identity is close. In pairs, in the channels.

As a result, we have less hassle. And a good spectrum. Identical in the channels.
 
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The complete identity of the shoulders is not only unrealistic. But it is not necessary.
It is more important that the non-identity is close. In pairs, in the channels.

As a result, we have less hassle. And a good spectrum. Identical in the channels.
Naaaah... Sure, the cancellation of the even order harmonics is not 100% perfect, but it should still work. The 2nd harmonic should be a lot lower.
 
I finally got USCi. I measured them with a multimeter. The gate has a resistance greater than 2 mΩ. D-S shows resistance-full zero. Probably because SiC Normally-On Junction Gate Field-Effect Transistors. The Chinese device identified them as two diodes.🙂
 

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Hi, Jonathan!!! I have already turned on the amplifier on the USCi.
If the voltage across the USCi gates is 8.9 V, then the current is 140 mA. The frequency response is linear (0 dB) up to 400 kHz. Found two nuances. When all power supplies are turned on at once, a large inrush current is generated. We'll have to make the USCi power-on delay. And the USCi current increases slightly as it heats up, but I will still closely watch the current increase.
 
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A good result was obtained with the 2SK1530.
But now it will be difficult to find original ones. Here is a photo of the original 2SK1530.
There should be a dash where - Note 2 and JAPAN is slightly shifted to the left.
 

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Well that is an easy fix for the MOSFET. Are you referring to the Toshiba 2SK1530 when you say MOSFET?

I am trying to find the combination for best sound now that I have boards in hand. I also have Vishay IRFP150PBF as well as Exicon ECX10N20-S.

Are all USiC off the table now? What about the UJ3N065025K3S? It appeared you had some success with that jfet earlier on. Did it also require the turn-on delay?
 
ECX10N20-S are good transistors for sound, but would it be better to put the IRFP150PBF first? Alexey Semin worked with UJ3N065025K3S.
They have a large capacity. Mosfet transistors IRFP264, IRFP150N and 2SK1530 have proven themselves well. But the 2SK1530 were the best. The circuit works better on MOSFET transistors.