Most Greedy Boy, of them all... or (there is no) DEFiSIT of Papa's Koans

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.........
 

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Official Court Jester
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while I was sorta waiting to get it on temp , listening tuner , solving drek connection on Tanns , my friend Woland newly acquired ;

bass connection will be ditto on original soldering eyelets , while I moved squawker wires to newly made solder pads , mounted on one spider ring bolt

later I switched to my workshop CD-DAC as source
 

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Official Court Jester
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in more words ...... something as bstrd of SIT-1 and M2 :rofl:

as I wrote on Baby DiyA - from all sane FW amps (most of them I had on my handy chipboard test-bed, either mono or stereo ) , Babelfish J2 is the best , while M2 is definitely dearest

in my world , those two aren't mutually exclusive

SIT-1 , SIT-2 and , I strongly believe, now - DEFiSIT - are excluded from list of sane FW amps

We've seen everything from Pa ....... some amps are all wit , some are all quirk ..... but those 3 are Demonstration of Force

pretty much as XS Bigguns in PL Coral , but I didn't had opportunity to squeeze these on my chipboard

:)

back to little one

words

Spooky

Just Right
 
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introducing source resistors and optocoupler between gates , allows any specimen of chosen parts to be used in circuit (same as in M2 ) not just painstakingly selected ones , as in DEFiSIT presented on BAF (and here)

edit ....... ha - that means Papa can toss in , all lefties and righties of Pass-SIT-1

:devily:


.......
:rofl:

if he change name to DEFiSIC , he can use that vagon of SJDP
 
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how to stack two potted and shielded Donuts

had two identical ones , with threaded Aluminium insert , for 6mm bolt ;

that's left pic

took one , drilled with 8mm bore through center of insert and all the way , then took 12mm bore , and increased hole on top of top shield half , to prevent any possibility of contact with bolt body, thus no possibility of short circuit

took two rubber rings , for placing one beneath and one in between Donuts

took proper length 6mm bolt , stacked them and that's it

that's right pic

short piece of wire soldered to each of 4 pans , all 4 soldered to one wire , routed to main chassis bolt (back left rubber foot bolt; star washers necessary)

645815d1510689568-greedy-boy-defisit-papas-koans-18-jpg
 

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thinking about establishing my own Review Site .........

but, considering how I'm lazy for scribings , despise FiFi vocabulary , and squeamish of that all ........

naah .... better to leave all that to less squeamish ones
 

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there is input cap too

buffer and xformer are DC coupled , rest of xformer is DC decoupled from GND

gates of JFet buffer are elevated somewhat bellow Ub/2 , so their sources , so entire xformer winding ........ DC coupled to output's gates , so their sources are at Ub/2

reminder : P mosfet demanding gate approx. 4V lower than source , for being able to conduct ; thus entire (red) biasing route need to be at (Ub/2)-4V
 

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thx for the drawing :)

instead of dc coupling the autoformer to the buffer and lifting it off ground the autoformer could have been tied to ground and decoupled from the buffer - just as in the M2. The biasing would then need to happen after the cap, just as it does in the M2.

Here, the biasing happens before the buffer, but doing it this way comes at the expense of an input cap so I suspect there is an inherent advantage. What is it?
 
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.....

Here, the biasing happens before the buffer, but doing it this way comes at the expense of an input cap so I suspect there is an inherent advantage. What is it?

well , I'm the one who is obsessed with DC coupling , but Papa obviously isn't

everything is much simpler , when you decide to use cap or two


ZenMod are you able to reveal the configuration of the powersupply?

It looks like it might be a variation on the F6/F7 supply.

dunno what will be for production iteration , but this one is CRCRC ; that's pretty much enough ....... we (greedy Boyz) are anyway used to choose our poison , same as size of it