Waiting on parts again and waistin time thinkin and had a question. I was impressed with what Nelson has accomplished with BA-3 and thinking of other interesting circuits that perform well and are still simple. One that comes to mind is the Circlotron article by Rothacher. The distortion numbers are very good and get even better with a nice device like the SS fets. Question is, can something like this be used as a VAS instead of the usual standalone power amp or output stage. Bigger easier load than speaker. Numbers should only improve with smaller die parts. LU jfets have been used successfully in DAO follower. Even the 2013 would be a candidate. BF862, J310. If possible, could be very nice. Clean power would be important. I will scribble on paper while out of town. Probably should burn it as waste of time. Even if possible, i probably couldn't get it to work. Still figuring out biasing of Jfets
Little light on the subject that makes things interesting.
I mentioned it because it's an interesting example of how
things work - the output device is actually driven by the
voltage across the resistor with current provided by the
input JFET. This voltage has been bootstrapped by the
output, so now it depends on the gain of the output
device.
So you have to ask yourself - is this really a follower?
Couple surface observations or questions, whichever. Single stage circlotron, operated as source followwer is basically power buffer with current output determined by bias choice. Operated as common source, it is transconductance amplifier(quasi buffer), with gain of fet determining current to load. In both cases, it is just supplying current to load, thus the need for second stage. For V gain
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