Here is a funny little amplifier: it is an otherwise rather banale CFB symetrical amplifier with MOS output, but one aspect is unusual: it uses an autobias mechanism comparable to that of the Circlophone, adapted for vertical symetry operation rather than lateral in the Circlophone.
Performances are not great but sufficient, and it should be relatively easy to build.
I haven't tested it in reality (and have no intention of building it).
Have fun!
PS
I forgot to mention a notable feature: the OP topology is common source, meaning it is almost rail to rail
Performances are not great but sufficient, and it should be relatively easy to build.
I haven't tested it in reality (and have no intention of building it).
Have fun!
PS
I forgot to mention a notable feature: the OP topology is common source, meaning it is almost rail to rail
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I suppose it could work perfectly: at present, the loop gain is only ~20dB, and adding some more loop gain and as a consequence NFB (explicitly or by stealth as in the xyz-EC schemes) would improve matters greatly and pose no difficulty.
But then, you would also correct the character of this amp out of existence, and replace it with that of the OPA134 or similar you use for the correction.
This type of amp, having a strong character of its own, is best left alone. Would you think of applying correction to a SE triode amp? I don't think so.
Here, the main gain stage is the common source OP, comparable to a conventional tube PP. I think this would make it an "interesting" amplifier to listen to.
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Elvee, you said recently that you tend to prototype everything - why you didn't build this one to try it out ?
Yes, I did. As a result, I am now submerged with thousands of prototypes I built along the years, and I am totally clueless about most, since I have completely forgotten about them, and the paper documentations are dispersed between tens of notebooks or flying sheets, a total of thousands of pages without any order or classification system.
At the moment, I am trying to sort and figure out what everything was about, but in general it looks completely alien. I think I must have been seriously mad.
For that reason, I am momentarily calming down as I try to make room for the next wave....
Thanks, that's the way I'd like to picture myself.
Unfortunately, the reality is somewhat different and boils down to mental health issues: obsessive/compulsive behaviors, addictions, etc, and things do not improve with time....
He he 🙂
"Reality is what happens while we are dreaming of something different."
"There is two categories of people: Barbarians and others. Barbarians catch the things for their own profit when they are at hand, the others try to build the world at their image."
May-be you were not lucky enough to be born a barbarian ? There is no cure for that.
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