Simplistic NJFET RIAA

[Salas]

No, its wrong. Don't Eagle anything more till I give you your final circuits.

[SGregory]

OK. It was good practice to get back up to speed with Eagle again so it wasn't wasted work.

[SGregory]

Salas, Thanks for your offer. Here is the Idss of the pairs Ihave choosen

Q1 = 0.0102mA
Q2 = 0.0088mA
Q3 = 0.0100mA
Q5 = 0.0065mA

The cartridge is a Denon DL-103R.

I look forward to your suggestions for design.

[Salas]

Impossible. Do we talk in Ampere maybe? I need 4 pairs in between 7-10mA.

[SGregory]

Correct, the proper unit is Amps.

I have a pair for each Q1, Q2, Q3, and Q5 at those currents listed above. From the pdf, I thought that Q1 and Q3 should be the highest Idss, Q2 should be between 8-9mA and Q5 should be low somewhere in the neighborhood of 5-6mA.
If Q5 needs to be > than 7mA I have several pairs that match up 7.3, 7.4, 7.6, 7.7mA.

so to type correctly with proper units.
Q1 = 10.2mA matched pair
Q2 = 8.8mA matched pair
Q3 = 10.0 mA matched pair
Q5 = 6.5mA matched pair with options to go higher if needed.

[Salas]

OK, tomorrow you will have your double jfet cascoded headamp phono with staggered idss pairs and b1 style ac coupled buffer cct with max gain possible to wake up your 103R, plus a properly wired remote sense V1.0 reg with adjustable Norton Vref, not Zener.

[Salas]

Originally Posted by SGregory

Salas, Thanks for your offer. Here is the Idss of the pairs Ihave choosen

....

The cartridge is a Denon DL-103R.

I look forward to your suggestions for design.

Here you are, good luck, and let us know.

[massimo]

So the new "B1 style" buffer has become official?

[NPower]

Hello Salas
What is the main difference between previous RIAA filter and this one ?
Previous
R3-43K
R4-6.8K
C3-16nF
This one
R3-47K
R4//R12-6.8K+1M
C3-15nF

Brgds

[Salas]

Originally Posted by massimo

So the new "B1 style" buffer has become official?

Maybe, it plays OK and I had spares to put there. SGregory has spares and needs gain. I used it in my LMC so not to lose a few mVRMS too, since it has almost infinite load. I haven't done an exactly same build with and without so to tell. Since its load is a two legged made device it can be exchanged with a resistor and evaluate in a build.