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BAL to UNBAL DAC buffer

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revintage

revintage

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Joined 2007
#1
Kind of instrumentation amp. Any clues if the good simmed results are valid IRL?
 

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#6
Franz Gysi said:
Supersymetry 🙂

BTW: I miss the grid resistors (grid to ground).

Franz
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Hey Franz,
Yep I know of Pass Suzy(even not in detail), just couldn´t figure out how Zen Mod wanted to apply it here😱.

About the gridresistors, none are needed as the DAC is DC-connected and bias the grids to +2,5V. With over 5V on the cathodes no negative supply should be needed for the CCS.
 
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#9
Maybe not for the ones with an arrow inside a circle Who makes them?
Click to expand...

Will also work with a single BJT CCS. With over 5V DC and a signal of under 1V no problems will occur😉.

I used a similar circuit on my CD63
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Finally found your amp and found it farfetched to call ours alike🙂. But sure, you used two triodes and took the output signal from one of them. Maybe you changed the circuitry later in the thread as the one I found looked rather basic. Can you show it again?
 
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#10
revintage said:
Will also work with a single BJT CCS. With over 5V DC and a signal of under 1V no problems will occur😉.



Finally found your amp and found it farfetched to call ours alike🙂. But sure, you used two triodes and took the output signal from one of them. Maybe you changed the circuitry later in the thread as the one I found looked rather basic. Can you show it again?
Click to expand...

Yes, the diagram on the thread is basic, to say the least !!

The input was modified from T-L's published circuits and the triode stage was better developed, of course.

Sorry, I can't be more explicit at the moment ... most of my stuff and the final stage is in storage.


Andy


.
 
#15
analog_sa said:
I am very curious if anyone has taken measurements in support of this. My understanding is that most current sources underperform at drops less than 15-20v. Something to do with non-linear capacitances of the junctions.
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Have heard that MOSFETs should have an ample voltage margin. These are also known to have high capacitances all over😀.

Have though seen quite a few single smallsignal-BJT CCSs used down to something like 3-4V.
 
#18
tried or not - that's usual praxis in pro electronic - when using full balanced stage , as bal/unbal or unbal/bal convertor .

just imagine XLRs on both sides ; with tying one leg to gnd , you get that side ( either input or output ) as unbalanced ; other side is still balanced .

depending on circuit , some even aren't functional , if unused leg isn't tied to gnd
 
#20
I didn't told you to do anything ; I just bring examples .

that stage I posted is , in fact , pretty generic one , without too much efforts in squeezing last % of finesse . if I tried to do that - you would see gyrators in anodes ..... :rofl:

just a question - did you simmed it , or tried in vivo ?

:cheers:
 
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