Simplistic NJFET RIAA

[SGregory]

I do have a 192R. Will try that in a day or so. I need to get a few more pressings under my belt first at this value. As I listened more tonight the initial impression wore off to a degree and the center stage filled in to a degree. What became more noticable was the solidity of the bass line. A good word would be more concussive. It isn't a tuby experience just that I percieved to feel it more.

 

[Salas]

Run it a bit more then. Lower values are certainly electrically well matched too, if its a 5 Ohm coil typical Lyra.

 

[nicoch58]

with my 5ohm I use 180r a bit unload but I like better in my system...

 

[vgeorge]

Ready to start soldering!

 

[merlin el mago]

Ready to start soldering!

RIAA teflons

 

[vgeorge]

I tried to this build to do my best!
The caps were very good matched also. Hopefully no micas bypass.
In the shunt 1.2R I changed the 47uF capacitor to Silmic II and a little bit tighter layout.

 

[Salas]

That one is with the K170V jfets, yes? What is the measured value of your small Riaa capacitor?

 

[merlin el mago]

Did you purchase to Mark MPR right?

 

[vgeorge]

Yes, with K170V. The small ones are one 15,072 nF and the other 15,107. The 47nF came 46,96 and 46,96. R4 came 6,790 kOhm and R14 47,07 kOhm. Measured with my LCR meter.
Merlin, yes I bought them from Mark.

 

[Salas]

Fine values. Happy assembly. We will check again for bias voltages when running.

 

[Salas]

RIAA teflons

The Riaa caps ARE in the signal path essentially, its nice to pick good ones.

 

[Joshua_G]

Did you purchase to Mark MPR right?

Who is that Mark?

 

[merlin el mago]

Who is that Mark?

The person who sells the teflon RIAA caps in USA, link: Surplus USA Film Capacitors Teflon Polycarbonate Polyester Polypropylene

 

[merlin el mago]

Yes, with K170V. The small ones are one 15,072 nF and the other 15,107. The 47nF came 46,96 and 46,96. R4 came 6,790 kOhm and R14 47,07 kOhm. Measured with my LCR meter.
Merlin, yes I bought them from Mark.

Happy listening

 

[vgeorge]

Thank you very much Salas.
Picture to show progress so far.

 

[Salas]

Going well I see, but decouple those long incoming DC twisted pair wires right at the regs input connectors with some 0.1-1uF film cap each, also. I think its good practice. Or you are going to connect the M-Lytics for that?

 

[merlin el mago]

Going well I see, but decouple those long incoming DC twisted pair wires right at the regs input connectors with some 0.1-1uF film cap each, also. I think its good practice. Or you are going to connect the M-Lytics for that?

So the cap connected between input gnd & chassis gnd, right?

 

[df_genius]

has anyone got a stripboard layout that they can show us that works well? I'd love to build this cct but I haven't laid circuits out on stripboard much.

 

[Salas]

So the cap connected between input gnd & chassis gnd, right?

Wrong. Between +VIn and GND.

 

[merlin el mago]

Wrong. Between +VIn and GND.

Thanks to clarify