25W Single Ended Hammond 193V Choke Loaded 2SK180 L'Amp

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......You may not get the maximum power output though as the peak to peak output voltage at onset of clipping cannot be higher than the supply voltage.
.......

Yes, it can. The magic of inductive loads. The simulator knows this too :)

Yes, I understand that with choke loading, larger voltage swing can occur.

What I said was the "output voltage at onset of clipping", when the output signal is symmetrical and on the verge of going asymmetrical. My understanding is that the output voltage can go higher, but the output signal is then no longer symmetrical, resulting in high total harmonic distortion with large amounts of higher order harmonics. This is a situation that I would want to avoid. The part about "may not get maximum power output" is that the low V+ would not take advantage of the high power capability of the Tokin.

However I did not explain that.

I am an amateur doing diy and learning on my own, so I may have misunderstood the concept of choke loading if my statement is not correct. :confused: :)
 
34v p-p with a 25v supply. 35W in 4ohms @ 1.33% thd. For some reason the model i use indicates a much higher distortion than an actual THS51 on the bench but to be honest i have not measured this particular setup, due to the lack of a 5A capable choke.

Otoh, as already mentioned, a speaker choke of 10mH will be perfect in a bi/tri amping setup and this is inevitably forthcoming :)
 

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The output path S-D is connected to the earth via an infinitely small resistance via the power supply ...
and hence is parallel to the source choke.
In practice however there are differences. The trick is well known in tube land. The power supply residues might be less this way. And the HF effect could be quite noticeable, hard to simulate though methinks.
 
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34v p-p with a 25v supply. 35W in 4ohms @ 1.33% thd. For some reason the model i use indicates a much higher distortion than an actual THS51 on the bench but to be honest i have not measured this particular setup, due to the lack of a 5A capable choke.

Otoh, as already mentioned, a speaker choke of 10mH will be perfect in a bi/tri amping setup and this is inevitably forthcoming :)

I don't think I would connect the output of the circuit to speakers as it appears to have a 25VDC offset. Or is that a simulation issue and does not happen in real life?

The high THD that your simulation showed was due to clipping. I copied your model and simulated it and the output waveform showed a flattened bottom when zoomed in.

I also did some runs at lesser input/output voltages and although the waveform was not chopped off, the waveform was asymmetrical with the bottom compressed. The distortion profiles also showed large amounts of higher order harmonics, a sign of asymmetric non-sinusoidal output. As far as I can tell, the asymmetry started at peak to peak output voltage greater than 25V, but I may be wrong.

My simulations of the same circuit with the speaker return to ground gave the same peak to peak output voltages, except with so DC offset. So the AC output waveform was the same, as expected.
 
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But components are not ideal in real life. So the practical acceptable output signal voltage is somewhere in between, depending on the inductor, the Iq, and also on the listener's tolerance of distortion.

In general, it still seems to me that if higher output voltage is desired, higher Vds is advantageous.

It's been a great discussion, as it's been a learning experience.:)
 
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yes

all are depletion* devices, similar power, similar transfer characteristic

*if you are familiar with triodes- same nature as them, regarding biasing - normally fully open, you need to apply negative voltage at gate/grid (ref. to source/cathode) to decrease and control their conductivity/internal impedance

not same circuit, but you can observe graphs and whatnot in SInging Bush thread,, banging your head on graphs showing differences between 3 ( THF51, 2SK182, 2SK180) of them

I'm still banging my head on these graphs :)