Simplistic NJFET RIAA

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merlin el mago

merlin el mago

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Joined 2009
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Hi Lee

RIAA spreadsheet link "kabusa"

http://www.kabusa.com/riaa.htm

Enjoy

Cheers
Felipe

Thomo said:
I've just tweaked the resistors on my original board to the values shown in the pdf file hosted earlier in the thread. I also have a shuntreg built on veroboard which has been untested for a couple of years, so hopefully I can have a listen later today.

Ricardo, are you still following this thread?

Lee.
Click to expand...
 
Salas

Salas

diyAudio Chief Moderator
Joined 2002
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Joshua_G said:
1. Which version will have lower noise and better sound, your 60-63dB version, or your 36-46dB version + your pre-pre?
2. Wouldn't your pre-pre benefit from your Shunt Reg.?
3. Is there a benefit in adding capacitance multiplier after a Shunt Reg.?
Click to expand...

1. Best will be the pre pre + the recommended 45dB, bar the K170V 1R Rs double Jfet that the Swiss Franz guy once did. Don't mix individual targeted tweaks for Idss and cartridges I prepared for members with the meaning of version. The last general recommended ones are in the update/evolution link in post #1. Will copy the pre pre there too I guess.
2. You can feed it 9V with a dropping/cleaning RC filter from the general B+ coming from the shunt reg as a pre reg if integrated in same box/pcb, skipping 7809. Dropping R value/wattage will be determined of what main B+ is used and pre pre's 14mA draw.
3. In the very first stage for LMC yes. There will be 10-20nVrtHz at least from even best regs. Even if you make the shunt with ROHM or Hitachi super low noise TO-92s in its gain loop error amp. Its very good for noise but we need further local filtering to ensure we exploit the input fets spec for 0.2mV-0.25mV PITA carts. Lovely tone wimps non the less.
 

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merlin el mago

merlin el mago

Member
Joined 2009
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Schematics & psgr pdf

Links for schematics:

63db-Version 10,5mA IDSS Post 2795 output cart 0.25mV
Simplistic NJFET RIAA

60db-Version 8,2mA IDSS max. Post 3138 ouput cart 0.4mV
Simplistic NJFET RIAA

60db-Version 11.0mA IDSS for DL103 R Post 3767 ouput cart 0.25mV
Simplistic NJFET RIAA

60db-Version 8,5-8,7mA IDSS Post 3069 output cart 0.25mV
Simplistic NJFET RIAA

56db-Version 8,0-9,0mA IDSS Post 1814 output cart 0.25mV-0.5mV
Simplistic NJFET RIAA

55db-Version 6,6mA IDSS for Lyra Dorian Post 4141 output cart 0.6mV
Simplistic NJFET RIAA

52db-Version for 0,5mV MCs Post 236
Simplistic NJFET RIAA

48db-Version 8,0-9,0mA IDSS Post 1813 output cart 0.8-1mV
Simplistic NJFET RIAA

46db-Version for Benz ACE Post 240 output cart 0.8mV
Simplistic NJFET RIAA

43db-Version 4,0mA IDSS Post 4600 MM output cart 4mV
Simplistic NJFET RIAA

41db-Version 8,0-9,0 mA IDSS Post 1812 output cart 2-5mV
Simplistic NJFET RIAA

38db-Version 4,0 mA IDSS Post 5118 MM output 4mV
Simplistic NJFET RIAA

36db-version 7,0-8,0 mA IDSS Post 417 MM 3.5mV
Simplistic NJFET RIAA

pgsr pdf Links for schematics:

63db-Version 10,5mA IDSS Post 2795 output cart 0.25mV
Simplistic NJFET RIAA

60db-Version 8,2mA IDSS max. Post 3138 ouput cart 0.4mV
Simplistic NJFET RIAA

60db-Version 11.0mA IDSS for DL103 R Post 3767 ouput cart 0.25mV
Simplistic NJFET RIAA

60db-Version 8,5-8,7mA IDSS Post 3069 output cart 0.25mV
Simplistic NJFET RIAA

57dB-Version 8-8,5mA IDSS Post 4945 output cart??? MC
http://www.diyaudio.com/forums/analogue-source/129126-simplistic-njfet-riaa-495.html#post2308275

56db-Version 8,0-9,0mA IDSS Post 1814 output cart 0.25mV-0.5mV
Simplistic NJFET RIAA

55db-Version 6,6mA IDSS for Lyra Dorian Post 4141 output cart 0.6mV
Simplistic NJFET RIAA

52db-Version for 0,5mV MCs Post 236
Simplistic NJFET RIAA

48db-Version 8,0-9,0mA IDSS Post 1813 output cart 0.8-1mV
Simplistic NJFET RIAA

46db-Version for Benz ACE Post 240 output cart 0.8mV
Simplistic NJFET RIAA

45db-Version 8,0-8,5mA IDSS Post 4945 output cart??? high MC-MM
http://www.diyaudio.com/forums/analogue-source/129126-simplistic-njfet-riaa-495.html#post2308275

43db-Version 4,0mA IDSS Post 4600 MM output cart 4mV
Simplistic NJFET RIAA

41db-Version 8,0-9,0 mA IDSS Post 1812 output cart 2-5mV
Simplistic NJFET RIAA

38db-Version 4,0 mA IDSS Post 5118 MM output 4mV
Simplistic NJFET RIAA

36db-version 7,0-8,0 mA IDSS Post 417 MM 3.5mV
Simplistic NJFET RIAA

20db-Version 7mA IDSS Post 4945 Low MC pre-pre output cart 0.25mV
http://www.diyaudio.com/forums/analogue-source/129126-simplistic-njfet-riaa-495.html#post2308275

20db-Version 8.5 or 7.5-9mV IDSS Post 3695 Low MC pre-pre output cart 0.4mV 9V battery powered
http://www.diyaudio.com/forums/analogue-source/129126-simplistic-njfet-riaa-370.html#post2195237

psgr pdf Post 2706 (thanks to Ikoflexer) can be downloaded here: http://www.cs.toronto.edu/~relu/audio/salas/Salas-Riaa-Package-V1.zip

Cheers

Felipe
 
Salas

Salas

diyAudio Chief Moderator
Joined 2002
Paid Member
Joshua_G said:
Thanks, Salas.
How about having 3 2SK170 in parallel on the pre-pre?
Click to expand...

Too much gain in the pre pre's case. There are no degeneration resistors. If OTOH you make them GR to keep the transcoductance at bay, you lack on noise again. In general to realize less than what 2 devices like that can do in a simple practical build, really exploiting 4-8, the measures around them are becoming heroic. Then even the simple multiplier ain't enough.
 
Joshua_G

Joshua_G

Member
Joined 2008
gomeh.com/
Salas said:
Too much gain in the pre pre's case. There are no degeneration resistors. If OTOH you make them GR to keep the transcoductance at bay, you lack on noise again. In general to realize less than what 2 devices like that can do in a simple practical build, really exploiting 4-8, the measures around them are becoming heroic. Then even the simple multiplier ain't enough.
Click to expand...

Sorry, I don't understand. Can you please rephrase it?
 
Salas

Salas

diyAudio Chief Moderator
Joined 2002
Paid Member
Joshua_G said:
Sorry, I don't understand. Can you please rephrase it?
Click to expand...

It will give much gain for a pre pre if you parallel more fets I said. And if you use K170GR to keep the current and Gm the same, noise will be almost like with 2xK170BL. To really go very low en, general integration of techniques for PSU cleaning and circuit PSRR redesign will be out of this thread's concept. For practical vinyl replay purposes, this level of noise is very good to most users.
 
Joshua_G

Joshua_G

Member
Joined 2008
gomeh.com/
Salas said:
It will give much gain for a pre pre if you parallel more fets I said. And if you use K170GR to keep the current and Gm the same, noise will be almost like with 2xK170BL. To really go very low en, general integration of techniques for PSU cleaning and circuit PSRR redesign will be out of this thread's concept. For practical vinyl replay purposes, this level of noise is very good to most users.
Click to expand...

Thanks.
So, it seems like it will be beneficial to cascade the 2 x K170 in parallel, or to add a CCS for the B+, for the sake of better PSRR. Is that right?
 
Salas

Salas

diyAudio Chief Moderator
Joined 2002
Paid Member
Thanks for collecting the various schematics Merlin, but without the what and how of each one its possible they will overwhelm the casual visitor. They are just a collection of adaptations to specialities. Values revolving around IDSS stash and sensitivity needs or priorities of individuals. Variations on a theme. Useful for picking especially if having some whatever Jfets or cart. Those linked from post one are well grouped and ironed out though. And should be the ones to be considered general.
 
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