Amplifier building works this way. Either you build something published by Nelson Pass or Michael Rothacher, because they have at least built one working prototype. So these circuits work.
Or you roll your own, and then it is nice to do some simulations of course. But simulations only bring you so far. At one point in time you have to solder up your precocious silicon (or silicon carbide) to measure on, and to listen to the real thing. You have to take this risk. You are now into amplifier design, and everybody who have designed something have also seen the smoke coming out, one way or another. (You know, these machines work on smoke, now and then the smoke is let out, and the machine stops working!)
Ah.. But often design, of course, is really modifying and building upon some earlier work. That gives you a platform, you won't design some revolutionary new circuit of course, but you will end up with your own new design! (For example, maybe you could use a tube as a front end to these SITs? I have not seen anybody do that yet.)
Good luck with your amplifiers!
Or you roll your own, and then it is nice to do some simulations of course. But simulations only bring you so far. At one point in time you have to solder up your precocious silicon (or silicon carbide) to measure on, and to listen to the real thing. You have to take this risk. You are now into amplifier design, and everybody who have designed something have also seen the smoke coming out, one way or another. (You know, these machines work on smoke, now and then the smoke is let out, and the machine stops working!)
Ah.. But often design, of course, is really modifying and building upon some earlier work. That gives you a platform, you won't design some revolutionary new circuit of course, but you will end up with your own new design! (For example, maybe you could use a tube as a front end to these SITs? I have not seen anybody do that yet.)
Good luck with your amplifiers!
I've not tried to come down on anyone, particularly Nelson for NOT having a data sheet. Please link where I have. What I have done is asked anyone if they did have some specs for the PASS-SIT-1. And yes, I expressed that I am quite surprised that SemiSouth did not provide Nelson a datasheet for a custom device for which he paid big dollars. If I paid a hefty amount for a batch of custom devices, I would have expected a datasheet of at least some description.
In your blog to which I linked above, you provided a model for the PASS-SIT-1. And you also note:
...so even though no specific types were mentioned, naturally I was expecting to see the new and improved PASS-SIT-1 model as well as the 2SK82 in the LA6 bookzine. Was that such an unreasonable expectation?
That's good to know. OK, I will;
Do you have PASS-SIT-1 parameters for your new model?
First off, I greatly appreciate all the articles you've written which I have read, including the "Simulating SITs" entry. I humbly respect your technical experience and abilities. What doesn't make sense to me however, is why a web application would be written in a version of html that isn't compatible with the majority of browsers that the majority of folks are using, such as FF, or IE?
Good enough to produce realistic results. I would hope for something on the order of a SPICE JFET or MOSFET model. What am I making? Audiophile amps/preamps, guitar/bass amps/preamps/processors. I am doing some fairly in-depth research at the moment, and since I have great respect for NP's design experience and ears, I trust his critiques of the devices he works with, including the PASS-SIT-1. I'm looking to fully characterize the SIT's for comparison sake. My research thus far indicates that SIT devices may not be the only holy grail of amplifier devices as many espouse.
I'll never understand why so many have such hostility towards SPICE simulation and those that use it.
But no, I don't think I'm one of those "sim guys" (although I use simulation extensively in many areas of research and design), whoever those "sim guys" are to which you refer.
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I'm not new to forums, and I know a troll when I see one. The moderators here are consistent in asking members to stay on topic and focus on the facts. I have complied until reply #156; has he?
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Thanks, I'm glad we could end that on a friendly note, so here's an olive branch for your research:
I'm finding that the more modern Sic devices (mostly planar) model better with Koren and the older buried-gate stuff works pretty well with the concise model. Not that we have a big sample of modern device curves to look at, which makes it more challenging. So, we find something that suits our particular need and then we get on with the business of making amplifiers.
Best,
Mike
I'm finding that the more modern Sic devices (mostly planar) model better with Koren and the older buried-gate stuff works pretty well with the concise model. Not that we have a big sample of modern device curves to look at, which makes it more challenging. So, we find something that suits our particular need and then we get on with the business of making amplifiers.
Best,
Mike
I'll stick with the Koren model for the PASS-SIT-1 then, thanks.
I am intrigued by the smoothly-incremental, "symmetric" output curves of the SIT-1 (should produce a strong 3rd harmonic at onset of limiting) compared to the typical asymmetrical curves of the 2SK82 (which should produce mostly 2nd harmonic).
I am intrigued by the smoothly-incremental, "symmetric" output curves of the SIT-1 (should produce a strong 3rd harmonic at onset of limiting) compared to the typical asymmetrical curves of the 2SK82 (which should produce mostly 2nd harmonic).
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