Simplistic NJFET RIAA

diyAudio Chief Moderator
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Tonight or tomorrow. But you could try yourself independently also, since there are subjective things to consider about the rail impedance changing too beyond surely more DC power line isolation. Me I haven't got any filter whatsoever already installed passive or active to compare anyway. So it will be just raw vs one BJT Cmult 2nd order based. Two of those, one for each channel's DCin of course. All capacitors >=50V.
 

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Tonight or tomorrow. But you could try yourself independently also, since there are subjective things to consider about the rail impedance changing too beyond surely more DC power line isolation. Me I haven't got any filter whatsoever already installed passive or active to compare anyway. So it will be just raw vs one BJT Cmult 2nd order based. Two of those, one for each channel's DCin of course. All capacitors >=50V.

Hi Nick, so i should just try the KM without the RC net work?.
 
diyAudio Chief Moderator
Joined 2002
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I had so much trouble in the past dealing with hum from gnd arrangements and finally determined a basic connection that works very well. Yours is somehow different so I worried. Now I know it works perfectly.... :)

I am always learning.

I had taken the trouble to totally plan, guide, and supervise the layout (poor CRT I tortured him doing the CAD work) and to test build boxed assemblies in fully wired stereo scheme during last August so to ensure whatever I will suggest in the guide ain't wishful thinking. Grounding, oscillation, temperature, adjust, sound check. Tea bag Mike helped with feedback as self-volunteer "clueless" proto builder also. So to verify execution difficulty level is sensibly friendly as well.
Its the only way to make a sensitive thing like a no feedback loop discrete phono stage that can do MC predictable for a wide range of builders skills. I thought the parts selection and any PSU extravagance should be the builders creativity area but on firm ground. I hope that kind of approach worked well enough in the end.;)
 
Hello,
I intend tu assembly the Salas Simplistic NJFET RIAA. My turntable is Thorens TD 160 BC Super and the tonearm is SME 3009 Improoved (fixed headshell).
I'm interested to learn your advice about cartridges that would be appropriate for my hardware and, eventually, adaptations of the actual Simplistic NJFET RIAA diagram, please.
Thank you, very much.
 
Hello,
I intend tu assembly the Salas Simplistic NJFET RIAA. My turntable is Thorens TD 160 BC Super and the tonearm is SME 3009 Improoved (fixed headshell).
I'm interested to learn your advice about cartridges that would be appropriate for my hardware and, eventually, adaptations of the actual Simplistic NJFET RIAA diagram, please.
Thank you, very much.

Price range? MM or MC?
 
KM pre-reg

Hi Nick , quick try with KM as pre-reg for FSP . Psychoacoustics effect but i do detect less noise with it in place and more enjoyable. I don't have 1000uf 50V thus use 680uF in C1 filter, C2 -cheap 470uf and output couple cap is 47uf/63V. Can i sub the output cap for 22uf film cap?
Quan
 
diyAudio Chief Moderator
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If you mean the one with single BD139 and three capacitors I posted, its not a KM, just a second order normal capacitance multiplier filter. What is the practical voltage drop across it? About 1.5V? Here is its theoretical PSRR with your now capacitor values. 22uF Cout does not spoil it enough. Should clean some rail incoming EMI noises better, why not. Are bass and dynamics still good?
 

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