Simplistic NJFET RIAA

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I get about 10v at the output follower, not sure if it's worth finding a correct idss ccs for exactly half the supply voltage.

I picked that one now I looked back to see about the TT resistors. Better late than never.:)

Comment is, you are not to get half PSU there. But 10-11V. So its correct. R11 keeps it about double what is left below R10 actually. Its to soft clip the low half sine at about 20-22Vpk-pk. I don't use 17V at Q4 to avoid gate leakage current and to have enough Iq for gm and Rload drop for needed gain.
 
What is C3? I hope not MKS. I see a suspicious "S".:D

But still Salas, this will be an iterative experience for the most of us - we'll probably grab what we have and then buy and hopefully find the investment worthy. Most of us that is... I already unsoldered the most of the resistors once since I got the feeling they weren't good enough. Now everything stays - my fun later to read thru the lot and decide if anything get switched out.

You have done a great job Salas - keep it up and please don't misunderstand me - the spread of components are spreading all over the spectrum because of... ?
 
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diyAudio Chief Moderator
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But still Salas, this will be an iterative experience for the most of us - we'll probably grab what we have and then buy and hopefully find the investment worthy. Most of us that is...

Yes but also keep a minimum standard regarding recommendations not to rediscover America.:) I have had this circuit in various versions and guises put in many systems along its development. Including extremely expensive TTs and commercial phonos both tube and SS also DIY like Itch, Steve Bench, Vacuum State, Thorsten, MPP Paradise etc. Vgeorge had a Xono in his system before, Tea had a Pearl II. So there is a knowledge base.
 
Yes but also keep a minimum standard regarding recommendations not to rediscover America.:) I have had this circuit in various versions and guises put in many systems along its development. Including extremely expensive TTs and commercial phonos both tube and SS also DIY like Itch, Steve Bench, Vacuum State, Thorsten, MPP Paradise etc. Vgeorge had a Xono in his system before, Tea had a Pearl II. So there is a knowledge base.

We will grow, much thanks to the simplistic. Hence my interest in the next GB :)

Regards
 
Interesting, but probably ok to mix nichions and silmics. I see that most have put an cap to C2Y even if their boards are not yet ready to test. Why? Please report.

But still, why populate 2Cy if one haven't listened to it beforehand? Don't be shy. I'm populating every Q I can find which might be detrimental...
But then again my cart, Denon 103R needs the most amplification. About loading - any out there pinned down the best loading for 103r? 200-220ohms?

Regards
 
But still, why populate 2Cy if one haven't listened to it beforehand? Don't be shy. I'm populating every Q I can find which might be detrimental...
But then again my cart, Denon 103R needs the most amplification. About loading - any out there pinned down the best loading for 103r? 200-220ohms?

Regards

Well i if i understood correctly the guide, the ideal value for the cap is 15.2nf
so most users use 1% 15nf cap plus trim cap to get closer to the ideal value
 
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I use 200-220R on DL103R. In some systems that may vary a bit if not with a very neutral TT or speakers. People start somewhere at 200pF C2Y probably putting 2x100pF? Hoping that C2 is 15nF spot on. Having 0.3% LCR I have seen 15nF 1837s deviating mostly on plus side like 15.1nF when they do. So when not able to confirm the exact total value, I recommend to also listen with 1x 100pF to 150pF cap only by lifting its one leg, even when the 200pF sounds OK. There could be more treble resolution to get without harshness even when all is OK, it simply could be better and you would not know. If the caps had conspired to lower than nominal you will feel its too bright right away and restore. If its initially too bright with 200pF you would feel to add pF anyway. Its fun, easy tune, nothing is hurt when C2Y is put on a convenient large spot with many pads for that reason.