John Curl's Blowtorch preamplifier part II

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Maybe there is some alternate explanation that you missed?

I'm using fear in a weak not clinical sense. Like not subjecting long held beliefs to a test you "fear" might prove them wrong.

Like my little passive one stage open-loop preamp, I would gladly accept suggestions on LP's that overload it with mis-tracking or whatever like the 40yr. lore warns. I have tried several audiophile standards with no issues. The bottom line is that I would invite proof with open arms that the simplest phono preamp (a V to I into an all in one R/C inverse of the pre-emphasis) somehow fails to fit the bill at some fundamental level.
 
here's my entry into the passive eq phono pre, Harman Kardon Citation 1, Stu Hegeman's design contribution with one of the early entries into audiophile design, called Hi-Fi in those days. I think it was 1959.

and not only that is was switchable between the different competing EQ's of the day, before universal adoption of RIAA.

product brochure
http://www.vintagevacuumaudio.com/s...on-tube-amplifiers-preamplifiers-brochure.pdf

Cheers
Alan
 
Well here is what I am soldering up at the moment. None of my own work, but a collaborative effort. Original idea* by Luckythedog, MC design by Russ White, MM conversion by Hans Polak. This takes passive to new highs with an RL turnover of around 316Hz before any active device. I like this because there is something to upset almost all adherents of various cathedrals of phono design.

The all discrete lot will hate the 8-legs
D.Self dislikes both the loading concept and the idea of balanced phono
No-one does trans impedance MM stages!

Hard to be in more of a minority. Hell it might even work 🙂. certainly a change from boring old gain, eq, gain.

*Like all ideas this is not new, but LD rediscovered it independently.
 

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I haven't, but Hans has and I trust his skills on LTspice infinitely more than mine. 290mH is only half the MM inductance as it is balanced (well sorta balanced).

George has been running the single ended version for a couple of months now.

I should note took me a couple of weeks to actually get my head around this as it goes against almost everything we have been told.

EDIT: just to avoid confusion L1,L2,R9,R10 is the cartridge impedance
 
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