I did not use a voltage reference but an optocoupler to set the bias the led senses the current passing through the upper fet source resistors and the phototransistor actuates the vgs seen by the upper fet in order to set and maintain the bias. A comparatively large capacitor in parallel takes care of the AC content and limits any adjustment of the bias to very low frequency.
If it is okay with NP I can post my schematic wich I believe is fairly close to the real j2 in a weeks time or so.
I look forward to this post.
I wonder why other newer precision shunt references and current sources from LT havent been tried? i'm working the LT3092 into a prototype circlotron, and may try one of the LT refs in the J2 facsimile when time allows. provided someone -posts a cct soon, i dont have enough time on my hands for the cloak and dagger needed to get it so far hehe
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Papa gave enough meet to cover that bone
any constant voltage circ will do the job , and there are plenty of variations .
what I personally doesn't want to see around is circuit with attached claim "same as Papa's" .
considering circumstances , thats matter of respect .
so , please - write and post about variations , not clones
any constant voltage circ will do the job , and there are plenty of variations .
what I personally doesn't want to see around is circuit with attached claim "same as Papa's" .
considering circumstances , thats matter of respect .
so , please - write and post about variations , not clones
J2 is better ;
in simple words - more livelier , more fine details , more fun
edit:
more means substantially more
in simple words - more livelier , more fine details , more fun
edit:
more means substantially more
I would have thought my post made it pretty clear i would be interpreting it (is there any other option?), just as i am playing with circs. comparing to the AJX when its finished is first cab off the rank. this is a long way in the future though, i have plenty on my plate and after AJX and SS circ is done its time to focus on speakers for a bit
need to get a variac to make this a bit less daunting also
need to get a variac to make this a bit less daunting also
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In the last link here:
http://www.diyaudio.com/forums/solid-state/148959-semisouth-sic-power-jfets-2.html#post2645820
<<Other hi-fi manufacturers, which cannot be named due to confidentiality agreements, are following in his (Nelson) footsteps, and are either evaluating SemiSouth’s transistors or starting to use them for low volume production.>>
I wonder, what they will come up with, and will they reveal their design principles?
http://www.diyaudio.com/forums/solid-state/148959-semisouth-sic-power-jfets-2.html#post2645820
<<Other hi-fi manufacturers, which cannot be named due to confidentiality agreements, are following in his (Nelson) footsteps, and are either evaluating SemiSouth’s transistors or starting to use them for low volume production.>>
I wonder, what they will come up with, and will they reveal their design principles?
I have a spare chassis, and PSU here and would like to build the J2 to compare to the Aleph J. Would some one PM me their version of the J2, or steer me in the right direction.
Something about this thread makes me uncomfortable, but I can't stop watching it. It's like watching a traffic accident unfold at an intersection.



Yes, a description that describes the problematic of the situation .....
My suggestion is that Mr. Pass may allow Zen Mod to publish his Babelfish J2 over the store .....😎
Clearer situation, no original, but an outstanding solution with the same elements....
I hope I am not too keen as a youngster here......😉🙂😀
My suggestion is that Mr. Pass may allow Zen Mod to publish his Babelfish J2 over the store .....😎
Clearer situation, no original, but an outstanding solution with the same elements....
I hope I am not too keen as a youngster here......😉🙂😀
Hey, and a few of us can confirm the Babelfish J2 works. First important step.
....boy does it work!!! 😎
and a few of us can confirm the Babelfish J2 works
I would count on it. ZM will make it work! That's what's scary. 🙂
I would count on it. ZM will make it work! That's what's scary. 🙂
...not scary....gorgeous !!!😀
I have no doubt it will be gorgeous in sound and looks, but does the rest of the world need to know how to build it while the FW J2 is still being sold?
I give less than a month before fake boards are on Chinese eBay.
I give less than a month before fake boards are on Chinese eBay.
I have no doubt it will be gorgeous in sound and looks, but does the rest of the world need to know how to build it while the FW J2 is still being sold?
I give less than a month before fake boards are on Chinese eBay.
...how is that going to happen ?
...how is that going to happen ?
How? Release any schema that is remotely associated with the Charachters "J" and "2".
Everyone knows the J2 is the bomb. I know it and I've never heard it.
Unless there is something in the pipeline that's better, this will create a major stir for boards.
In the end, I think it's a beautiful thing that we enjoy something as good as this, but not at the cost of diluting an in production retail product. It just rubs me the wrong way. I respect the brain power that went in to developing something like this- OEM or otherwise.
Roll the dice. I'll stop here.
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